1988 F150 Running Rich and bad!
#258
09-27-2009, 12:54 PM
#259
09-28-2009, 07:17 AM
#261
10-02-2009, 04:06 AM
Kart18, grab a beer, kick back and be prepared for a long reply. Please read the entire post before doing any testing I mention below. My organization skills and paragraphing are the pits. I tend to have thought diarrhea. I’ve been away on vacation. I noticed that you have checked and cleaned the idle air bypass valve but i didn’t see if you have replaced it by now. I have an 87 f150 5.0 efi dual tank with 184000 miles. Most of my experience with the IAV is that it will affect idle and start and has been my most frequent problem for the 22 plus I’ve owned the truck. Any time my mileage went below 16 mpg I changed the O2 sensor, my second most frequent. And third, the six armed monster tank selector valve or DFR (replaced 2). Fourth , right exhaust manifold cracked.
The IAV can cause the idle up, idle down, almost die, idle back up, die at stop when foot removed from gas pedal, long or stumbling start on cool morning only to start and run fine as day or engine warms up. Pressing on the gas during start may help. The problem starts out rather gradual and random and finally sometimes it wont start. I have tried cleaning them and even using WD40 followed by alcohol or acetone in the valve body with little or only temporary effect.
I have done the same to the solenoid or electrical part of the IAV by spraying wd40 in the plunger end and then using a tooth pick or the wd40 extender tube to work the plunger up and down many times to be sure it wasn’t sticking. Then follow that with alcohol to flush out the wd40 by pushing many times on the plunger again. Then blow dry with compressed air. I have never found the valve to stick or drag from the carbon, but I have found the solenoid to have problems. I have even saved old valves and swapped solenoids and bodies among them trying to get one to work.
I’m a cheap sort and didn’t want to fork out the 40 to 90 bucks they cost new. In the end I could only eek out a little more use,a week to maybe 3 months. You basically just end up wearing out the electrical connector . I can never get those dang connectors to unplug worth a crap. I end up breaking the locking ears and having to ty-wrap the connector to keep in connected. Most are so hard and tricky to disconnect I think they were designed by Iraqi torture squads.
I have changed about 6 of the IAVs . The original lasted about 5 years, the replacements about 2 or 3. I have also changed out about 5 of the O2 sensors and the mileage would go back to the 16 to 18 plus range. Be aware that silicone spray or grease can ruin an O2 sensor. Using silicone spray or grease in the throttle body or air intake can let silicone fumes end up in the exhaust then the O2 sensor or so I have been told. The main thing is to keep silicone fumes out of the engine compartment. They make low fume silicone greases.
I would do an electrical check of the IAV before replacing it. It should make a good solid thunk or click when it picks up. Watch the valve stem, there should be no delay as it moves either direction. To test I remove the IAV and connected it to a 12 volt spare battery I keep in my dungeon as sweetie calls it. Please be mindful that car or DC voltage relays may be polarity sensitive due to an internal free wheeling or reverse biased diode or surge protector now that we are in the computer age. Sometimes the diode is on the connector from the computer. Others may use a resistor across the coil or both resistor and diode. Connect the voltage wrong and it will blow open or short the diode. If blown open the relay will work fine but the computer output circuit might get fried later on from the couple hundred volts that itty bitty coil can produce when voltage is removed. Transient voltages produced when coils are de-energized can be many times the operating voltage.
If the diode fails shorted, it may overload the computer output . I can’t ever remember which terminal on the IAV is +, so I just unplug the iav, then turn the key on and measure the voltage between the two pins on the connector toward the computer. I note which is + and turn the key off and head to the dungeon. I use small alligator clip jumper leads to connect to both pins on the IAV. Then stick the other two ends to the appropriate battery terminals. I usually apply and remove the voltage several times to be sure it clicks right every time. I have had them to sound good 4 or five times then get a slow, weak, or no operation. Play morse code with it, send sweetie an sos but operate it several times.
Always remember to use a little dielectric or silicone grease such as dow corning 111 on the electrical connector seals and pins. I use a tooth pick or small swab to apply. It forms a good seal and keeps water out and prevents corrosion. Just don’t overdo it as it might trap air and pop the connector loose later. Been there done that. More ain’t better. It is especially important to use the grease on connectors for the small signal or low power type sensors such as, O2, map, maf, temperature, cam position, ignition, and others.
My experience with the DFR was random missing, bucking, hard start, and die. About a year ago sweetie informed me the truck was jumping or bucking occasionally. I told her it probably was just bumpy road. A few weeks later it did it with me. Took it to the garage and they found no problem. A week or 2 later on a 95 degree scorcher, sweetie called and said it died in the middle of the 4 lane and wouldn’t start back up, come get her. I told her I was busy at work ,use that AAA card. About 10 minutes later it dawned on me the error I had just made. I called Her majesty and she informed me I was lucky it started back up before she burned up the starter. I suggested she drive it to the garage and I was leaving work and would meet her there or where ever it died again. It made it to the garage. I told them to keep it a week or 2 to drive around if needed to find the problem. They said it purred like a fat cat the whole time they used it.
I got it back and I happened to remember I hadn’t changed the fuel filter in several years as I only drove it about 5 or 6 K miles a year. I cut the old filter apart and the crap that came out of it looked more like coffee and smelled like old gas. It ran fine with me for the next 2 weeks so I told sweetie its fixed. Wrong. It bucked , jumped and knocked then died in the middle of the road with her the next day. but I was with her. Lucky it was in a nice flat slightly down hill road with a nice place to pull to the side just past a big old puddle. I pushed, all she had to do was go past the puddle and ease it to the side.
About the time I guessed we should be passing the puddle, I was ankle deep. About that time she tried the starter again and it cranked. We was only half a mile from the house so I told her to keep going I would walk. It died and cranked again and she got it to the house. This time I regained presence of mind and never mentioned the puddle and the sweat down my butt crack. besides my feet were dry after walking on that 120 f pavement.
I called the garage and they said bring it in about 5 days. The next morning I remembered the FDR had that filter looking thing on the bottom and it was between the tanks and filter. Maybe it got some of that gunk too. Called the ford place and they had one in stock. I went and got it and stuck it on. Removed the filter looking thing that said don’t remove and there was a little bit of trash and rusty stuff. I wasn’t sure it was the problem and I had visions of just having blown $140 on that DFR. Cranked up and ran fine for the next several months. The fat cat purred.
Shortly after this repair, sweetie and I took my buddy and his wife out to supper. I had borrowed his wood chipper to grind up a huge pile of limbs at her old house we are fixing up. He was giving me heck about that cheap crap brown gas I put in his chipper. Then it all made sense. We had been using the truck a bunch more while cleaning up and remodeling her old house. It was summer and the days I was working she took the 2 grandsons over to her old house to work for some summer girlfriend money. There was a gas shortage at the time. I had filled my truck, the wood chipper, and 3 gas cans at wally world. It appears I got a bunch of gas from the bottom of the tank and it messed up the filter and DFR and wood chipper.
But wait I aint done. Grab another beer. Remember above I said that changing the IAV had always fixed my rough idle and changing the O2 sensor got my mileage 16 or more about 4 or 5 previous times? Well it didn’t work this last time about a month or 2 ago. So changing IAV, O2 sensor, plugs, distributor cap, rotor button, 2 temperature sensors, and a MAP only got me about 1 mpg. Worst mileage I have ever seen. It was about 13.4 and now 14.7. I still have the funky idle. But the IAV and fuel filter and DFR might work for you. It has for me in the past.
1) Did you have a gas shortage in your area a while back?
2) Have you changed your IAV
3) Did your problem show up shortly after installing the new fuel pump and sender assembly?
4) Is your exhaust header cracked? Depending on where and how the crack is shaped and located in the exhaust header, it could act like one of them air powered vacuum pumps and be sucking air in the exhaust through a crack or rust pit near the O2 sensor ? Mine only has one sensor in a small pipe welded between the 2 exhaust header outlets
5) Do you live in an area that uses a lot of road salt?
6) Do you spray clean your engine when its hot?
The IAV can cause the idle up, idle down, almost die, idle back up, die at stop when foot removed from gas pedal, long or stumbling start on cool morning only to start and run fine as day or engine warms up. Pressing on the gas during start may help. The problem starts out rather gradual and random and finally sometimes it wont start. I have tried cleaning them and even using WD40 followed by alcohol or acetone in the valve body with little or only temporary effect.
I have done the same to the solenoid or electrical part of the IAV by spraying wd40 in the plunger end and then using a tooth pick or the wd40 extender tube to work the plunger up and down many times to be sure it wasn’t sticking. Then follow that with alcohol to flush out the wd40 by pushing many times on the plunger again. Then blow dry with compressed air. I have never found the valve to stick or drag from the carbon, but I have found the solenoid to have problems. I have even saved old valves and swapped solenoids and bodies among them trying to get one to work.
I’m a cheap sort and didn’t want to fork out the 40 to 90 bucks they cost new. In the end I could only eek out a little more use,a week to maybe 3 months. You basically just end up wearing out the electrical connector . I can never get those dang connectors to unplug worth a crap. I end up breaking the locking ears and having to ty-wrap the connector to keep in connected. Most are so hard and tricky to disconnect I think they were designed by Iraqi torture squads.
I have changed about 6 of the IAVs . The original lasted about 5 years, the replacements about 2 or 3. I have also changed out about 5 of the O2 sensors and the mileage would go back to the 16 to 18 plus range. Be aware that silicone spray or grease can ruin an O2 sensor. Using silicone spray or grease in the throttle body or air intake can let silicone fumes end up in the exhaust then the O2 sensor or so I have been told. The main thing is to keep silicone fumes out of the engine compartment. They make low fume silicone greases.
I would do an electrical check of the IAV before replacing it. It should make a good solid thunk or click when it picks up. Watch the valve stem, there should be no delay as it moves either direction. To test I remove the IAV and connected it to a 12 volt spare battery I keep in my dungeon as sweetie calls it. Please be mindful that car or DC voltage relays may be polarity sensitive due to an internal free wheeling or reverse biased diode or surge protector now that we are in the computer age. Sometimes the diode is on the connector from the computer. Others may use a resistor across the coil or both resistor and diode. Connect the voltage wrong and it will blow open or short the diode. If blown open the relay will work fine but the computer output circuit might get fried later on from the couple hundred volts that itty bitty coil can produce when voltage is removed. Transient voltages produced when coils are de-energized can be many times the operating voltage.
If the diode fails shorted, it may overload the computer output . I can’t ever remember which terminal on the IAV is +, so I just unplug the iav, then turn the key on and measure the voltage between the two pins on the connector toward the computer. I note which is + and turn the key off and head to the dungeon. I use small alligator clip jumper leads to connect to both pins on the IAV. Then stick the other two ends to the appropriate battery terminals. I usually apply and remove the voltage several times to be sure it clicks right every time. I have had them to sound good 4 or five times then get a slow, weak, or no operation. Play morse code with it, send sweetie an sos but operate it several times.
Always remember to use a little dielectric or silicone grease such as dow corning 111 on the electrical connector seals and pins. I use a tooth pick or small swab to apply. It forms a good seal and keeps water out and prevents corrosion. Just don’t overdo it as it might trap air and pop the connector loose later. Been there done that. More ain’t better. It is especially important to use the grease on connectors for the small signal or low power type sensors such as, O2, map, maf, temperature, cam position, ignition, and others.
My experience with the DFR was random missing, bucking, hard start, and die. About a year ago sweetie informed me the truck was jumping or bucking occasionally. I told her it probably was just bumpy road. A few weeks later it did it with me. Took it to the garage and they found no problem. A week or 2 later on a 95 degree scorcher, sweetie called and said it died in the middle of the 4 lane and wouldn’t start back up, come get her. I told her I was busy at work ,use that AAA card. About 10 minutes later it dawned on me the error I had just made. I called Her majesty and she informed me I was lucky it started back up before she burned up the starter. I suggested she drive it to the garage and I was leaving work and would meet her there or where ever it died again. It made it to the garage. I told them to keep it a week or 2 to drive around if needed to find the problem. They said it purred like a fat cat the whole time they used it.
I got it back and I happened to remember I hadn’t changed the fuel filter in several years as I only drove it about 5 or 6 K miles a year. I cut the old filter apart and the crap that came out of it looked more like coffee and smelled like old gas. It ran fine with me for the next 2 weeks so I told sweetie its fixed. Wrong. It bucked , jumped and knocked then died in the middle of the road with her the next day. but I was with her. Lucky it was in a nice flat slightly down hill road with a nice place to pull to the side just past a big old puddle. I pushed, all she had to do was go past the puddle and ease it to the side.
About the time I guessed we should be passing the puddle, I was ankle deep. About that time she tried the starter again and it cranked. We was only half a mile from the house so I told her to keep going I would walk. It died and cranked again and she got it to the house. This time I regained presence of mind and never mentioned the puddle and the sweat down my butt crack. besides my feet were dry after walking on that 120 f pavement.
I called the garage and they said bring it in about 5 days. The next morning I remembered the FDR had that filter looking thing on the bottom and it was between the tanks and filter. Maybe it got some of that gunk too. Called the ford place and they had one in stock. I went and got it and stuck it on. Removed the filter looking thing that said don’t remove and there was a little bit of trash and rusty stuff. I wasn’t sure it was the problem and I had visions of just having blown $140 on that DFR. Cranked up and ran fine for the next several months. The fat cat purred.
Shortly after this repair, sweetie and I took my buddy and his wife out to supper. I had borrowed his wood chipper to grind up a huge pile of limbs at her old house we are fixing up. He was giving me heck about that cheap crap brown gas I put in his chipper. Then it all made sense. We had been using the truck a bunch more while cleaning up and remodeling her old house. It was summer and the days I was working she took the 2 grandsons over to her old house to work for some summer girlfriend money. There was a gas shortage at the time. I had filled my truck, the wood chipper, and 3 gas cans at wally world. It appears I got a bunch of gas from the bottom of the tank and it messed up the filter and DFR and wood chipper.
But wait I aint done. Grab another beer. Remember above I said that changing the IAV had always fixed my rough idle and changing the O2 sensor got my mileage 16 or more about 4 or 5 previous times? Well it didn’t work this last time about a month or 2 ago. So changing IAV, O2 sensor, plugs, distributor cap, rotor button, 2 temperature sensors, and a MAP only got me about 1 mpg. Worst mileage I have ever seen. It was about 13.4 and now 14.7. I still have the funky idle. But the IAV and fuel filter and DFR might work for you. It has for me in the past.
1) Did you have a gas shortage in your area a while back?
2) Have you changed your IAV
3) Did your problem show up shortly after installing the new fuel pump and sender assembly?
4) Is your exhaust header cracked? Depending on where and how the crack is shaped and located in the exhaust header, it could act like one of them air powered vacuum pumps and be sucking air in the exhaust through a crack or rust pit near the O2 sensor ? Mine only has one sensor in a small pipe welded between the 2 exhaust header outlets
5) Do you live in an area that uses a lot of road salt?
6) Do you spray clean your engine when its hot?
#263
10-02-2009, 09:04 AM
Post Fiend
#264
10-02-2009, 10:21 AM
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I can so relate to the problems with sweetie. Especially the puddle. LOL
My sweetie has taken to running into crap lately. Knocked the mirror off 2X at the same drive-through, backed into 2 Illegal aliens, ran over 1 dead deer, and orange barrels in the construction area.
The big argument the other day was, "I don't know why you wont let me drive your truck!". My answer was, "Well Crash, you look prettier in the van."
After the deer/orange barrels I have taken her driving privileges away. Now she's really angry. My Dodge Grand Caravan threw a party and the F-150 sighed, "Whew!"
Guess, I'll spend the rest of the day, dragging her butt to all of her appointments, errands, cart her mom around and wait for the insurance adjuster to come and look at the van.
What a day!
My sweetie has taken to running into crap lately. Knocked the mirror off 2X at the same drive-through, backed into 2 Illegal aliens, ran over 1 dead deer, and orange barrels in the construction area.
The big argument the other day was, "I don't know why you wont let me drive your truck!". My answer was, "Well Crash, you look prettier in the van."
After the deer/orange barrels I have taken her driving privileges away. Now she's really angry. My Dodge Grand Caravan threw a party and the F-150 sighed, "Whew!"
Guess, I'll spend the rest of the day, dragging her butt to all of her appointments, errands, cart her mom around and wait for the insurance adjuster to come and look at the van.
What a day!
#265
10-02-2009, 11:17 PM
Quicklook, it took me much longer to write all that crap out than to pull an IAV off and test it. about 3 minutes to pull the connector off and turn the key on to see which terminal of the IAV solenoid is +. then 2 minutes to remove it. and about 5 more to test it and send morse code. cleaning them takes about 15 to 30 minutes, but as i said above it dont get you much if any more use. Thats why you put the voltage first. but i usually clean any way. Most dont have the free wheeling diode only and arent polarity sensitive. if they have a resistor and diode or just a resistor they arent polarity sensitive. but I blew a new one once and blew that $60 so i just check to be sure.
Yep KC, sweetie is pretty much git in sit down shut up and hang on and be quick about it. She has pulled off with me hangin on the door a few times. ease forward or back slowly means gun it and slam the breakes.
Yep KC, sweetie is pretty much git in sit down shut up and hang on and be quick about it. She has pulled off with me hangin on the door a few times. ease forward or back slowly means gun it and slam the breakes.
#266
10-05-2009, 07:51 AM
gpedens - The answer to all your questions (6) is no. The truck is still at the garage. He want's to take a crack at it so I will wait and see what he comes up with.
I'm sorry it took so long to reply. I was off on Friday and at the Williams Grove National Open this week end. We were in the chili cook-off and just had more fun than a normal person has in a lifetime.
I'm going to wait and see what he comes up with. He had the truck before for a few days and I had to go get it before it was fixed. He was very adamant about getting it back. He is the type of person that doesn't give up till it's fixed and he didn't charge me a thing the first time around. So, if he doesn't come up with a fix then I will per sew other options. Thanks for the reply.
One question though - I have been told many times that the IAV only affects idle. The way you describe it, it seems to affect more than that???
Todd
I'm sorry it took so long to reply. I was off on Friday and at the Williams Grove National Open this week end. We were in the chili cook-off and just had more fun than a normal person has in a lifetime.
I'm going to wait and see what he comes up with. He had the truck before for a few days and I had to go get it before it was fixed. He was very adamant about getting it back. He is the type of person that doesn't give up till it's fixed and he didn't charge me a thing the first time around. So, if he doesn't come up with a fix then I will per sew other options. Thanks for the reply.
One question though - I have been told many times that the IAV only affects idle. The way you describe it, it seems to affect more than that???
Todd
#267
10-05-2009, 08:25 PM
Sorry to mislead you Kart18. I was a bit long winded. The IAV controls idle only or when you dont have your foot on the gas pedal. It can cause surging idle, hard start, die when you let foot off the gas, or no start. The other part in the long winded reply above was that fuel swapping valve on dual tank models before 1989. I think I saw they called it an FDR fuel diverter relay. I usually think of a relay as a solenoid or or coil powered by electricity. I would prefer the term FDV fuel diverter valve as mine has no wires to it. I have a dual tank 1987 f150. I've had to replace mine twice. the way the FDR done me was mostly at crusing speed. The truck would be running along fine then start bucking or missing for a few seconds and then go back to running fine. Sometimes it was a slight miss for several seconds then it would go back to running fine. It even died in the middle of the road but started back up shortly after. I think in my case it was bad trashy gas caused someting to stick in the FDR.
#269
10-20-2009, 04:32 PM
Hello to everyone! I have two things:
1. The garage checked the voltage from the computer to the O2 sensor - it is supposed to be +5 and it is -5. Would this cause the problem? Would
this send a lean code and actually be running rich? Would this cause the
bucking (motor cutting out while driving)?
2. Is there a way to know what computer I need without taking it out?
Thanks, Todd
1. The garage checked the voltage from the computer to the O2 sensor - it is supposed to be +5 and it is -5. Would this cause the problem? Would
this send a lean code and actually be running rich? Would this cause the
bucking (motor cutting out while driving)?
2. Is there a way to know what computer I need without taking it out?
Thanks, Todd
#270
10-20-2009, 05:40 PM
Post Fiend