Can't figure out this one.
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From: Norristown, PA
Can't figure out this one.
I posted a while ago about the way my truck starts; it will go into a high idle and the check engine light will flash. When I put it in Drive, the truck feels like it will stall. So someone mentioned the IAC. So I figured out where it was, removed it, sprayed it out with carb cleaner, reinstalled it and the truck seems to start better, but haven't tried it on a cold start. Anyway, I drove the truck around to see how it would perform and I noticed at low speeds, 20-30 MPH, with the gas pedal slightly pressed, I can hear the engine "putt-ing" through the exhaust. I don't hear that at higher speeds. I got the codes from the EEC and I think it's a 34 code. My Haynes manual states for 34 code: EVP voltage above closed limit - Perform EGR valve, EVR vacuum, EVR circuit, EVP circuit and EVP sensor checks. The manual does not list any intructions on how to perform all of these checks. I managed to remove the EGR. I removed the gasket, cleaned both surfaces, applied gasket sealer and reinstalled the EGR. Truck still "putts." I have purchased a new Ford IAC, but haven't installed it yet because I'm not sure that is the problem. Any ideas??
Joe
Joe
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From: Norristown, PA
Originally Posted by 73Fastbackv10
Check your tranny fluid. Your tranny could be stalling your engine.
Joe
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From: Norristown, PA
Originally Posted by jbondi
I posted a while ago about the way my truck starts; it will go into a high idle and the check engine light will flash. When I put it in Drive, the truck feels like it will stall. So someone mentioned the IAC. So I figured out where it was, removed it, sprayed it out with carb cleaner, reinstalled it and the truck seems to start better, but haven't tried it on a cold start. Anyway, I drove the truck around to see how it would perform and I noticed at low speeds, 20-30 MPH, with the gas pedal slightly pressed, I can hear the engine "putt-ing" through the exhaust. I don't hear that at higher speeds. I got the codes from the EEC and I think it's a 34 code. My Haynes manual states for 34 code: EVP voltage above closed limit - Perform EGR valve, EVR vacuum, EVR circuit, EVP circuit and EVP sensor checks. The manual does not list any intructions on how to perform all of these checks. I managed to remove the EGR. I removed the gasket, cleaned both surfaces, applied gasket sealer and reinstalled the EGR. Truck still "putts." I have purchased a new Ford IAC, but haven't installed it yet because I'm not sure that is the problem. Any ideas??
Joe
Joe
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From: St Louis
I used the borg and warner replacment even though it isnt exactly a ford part. I think it was less than 20 bucks and I had to use a gasket sealer to get the sensor to seal on top of the egr valve. I havent had problems with it since though. A hand vacuum pump that you use to bleed brakes is more than adequate to provide the necessary vacuum pressure to this valve.
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From: Norristown, PA
Originally Posted by jbondi
I just checked the EVP voltage, across the VREF and SIG-RTN terminals, and it's about 4.9 volts; book states 5 volts. I checked the EVP resistance across the EVP and VREF terminals and it was about 3700 -3900 ohms. The book says it should be about 5000 ohms. I don't have a vacuum gauge to apply 10 in. Hg. of vacuum to the EGR to see if the resistance drops. Has anyone ever bought a new EVP sensor? If so, where and how much? By the way, I started the truck this morning, after it sat all night, and the idle is fine. Cleaning the IAC worked. Now I have to return the new one I bought.
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From: Norristown, PA
Originally Posted by jbondi
I think I spoke too soon. The starting idle speed is still not right. So I replaced the IAC and have to test it on a cold start. I did replace the EVP and found no change with the "putt-ing" at low speed. My next move will be to either install a new cap and rotor and replace the EGR. Can anyone help me out here? Thanks.
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From: sunny fla sometimes windy
it will just vent the gas vapors out into your engine compartment on hot days so you will smell gas and could have an explosion risk make sure to run the charcoal canister line out of the engine compartment close to the ground. Otherwise it shouldn't really hurt anything leaving it disconnected. You could remount it closer towards the back by the gas tank so you don't have to worry about BOOM!!!
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From: Norristown, PA
Originally Posted by blue beast
it will just vent the gas vapors out into your engine compartment on hot days so you will smell gas and could have an explosion risk make sure to run the charcoal canister line out of the engine compartment close to the ground. Otherwise it shouldn't really hurt anything leaving it disconnected. You could remount it closer towards the back by the gas tank so you don't have to worry about BOOM!!!
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From: Norristown, PA
Originally Posted by jbondi
What would happen if I plug it? Cause a vacuum in the gas tank?
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From: sunny fla sometimes windy
Take off the intake hose at the TB and look at the butterfly. If it is open more than a c-hair someone probably turned up the hard throttle stop to help out the dirty IAC!!
Disconnect the IAC and start the truck if it stays at the high idle, Turn down that throttle hard stop until it is idling at around 500 rpm, reconnect the Iac it should go to around 750rpm. If that isn't it time to check the rubber gasket that the brake booster vac line plugs into, if it is cracked or torn replace it or silicone it. If the computer thinks you are trying to start it with the gas pedal pressed, it cuts back on the injectors opening so it doesn't flood out, so the hard throttle being misadjusted looks to the computer like you have the go pedal pressed!! Also look at the TPS the wires should be pointing at the IAC.
Disconnect the IAC and start the truck if it stays at the high idle, Turn down that throttle hard stop until it is idling at around 500 rpm, reconnect the Iac it should go to around 750rpm. If that isn't it time to check the rubber gasket that the brake booster vac line plugs into, if it is cracked or torn replace it or silicone it. If the computer thinks you are trying to start it with the gas pedal pressed, it cuts back on the injectors opening so it doesn't flood out, so the hard throttle being misadjusted looks to the computer like you have the go pedal pressed!! Also look at the TPS the wires should be pointing at the IAC.
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From: Norristown, PA
When I thought I was in the clear, I'm back having another problem. After replacing the cap, rotor and plugs a few weeks ago, the truck was running good. Now I'm hearing popping thru the air intake, slight hestitation and some knocking/pinging when I have to press on the gas to either merge into traffic or go up a hill. It doesn't happen all the time and it doesn't happen when cruising at a constant speed. I checked all of my spark plug wires and made sure they were tight. What else could it be??
P.S. I just changed the air filter, to a Fram paper filter, thinking my K&N OEM drop in filter had too much oil on it causing the engine to starve for air.
Help!!
Joe
P.S. I just changed the air filter, to a Fram paper filter, thinking my K&N OEM drop in filter had too much oil on it causing the engine to starve for air.
Help!!
Joe
