I'm no mechanic but have been around an engine or two and can do most things.
First some history. The van was given to me , free and clear.The owner had had issues with it and had decided on a new van. He had already replaced a few parts, including the solenoid( You can see this is new, it's on top of the engine block) .
When I first got it last fall, it ran ALOT better than what it did. It ran smooth even. However the check engine light did come on, and when it got hot ( like driving it the 80 km's to ottawa and back) it would stall out at corners.
I parked it for the winter, starting it occasionally reasoning I would work on it in the spring.
I replaced the wires, plugs, air filter and fuel filter. Even before I did this I noticed it was running aweful I had had to move it and it sputtered and croaked almost continuously.I took it down the road, and before and after the wire/plug change it would "GAG" or "bog" when I put the pedal down, even when it was idling in the driveway.
Along the lines i noticed a vacuum tube with what I THINK is a PVC valve was not seated in it's spot in the valve cover( left side of engine as you look from inside throught he access hatch).I reseated it , it just kinda sits in the hole with nothing to hold it in place. No change.
I took out the MAF sensor on the air intake, it looked clean but I cleaned it anyway. I also removed the throttle position sensor off the top of the throttle body, I can't see much with it it's basically kust a turn pot. I had read that there was a testing proceedure but I can't see a way to perform it since the wire colors don't seem to be the same and even if they were how to connect the wires to my digital voltmeter to perform the test with te connector?. I'm assuming it's good but that may be a mistake.
The vehicle seems to be getting worse and worse. It wont idle now unless I give it gas and it rattles and shakes, like it's misfiring but I don't think that is it. I doubt the engine has enough strength to mov ethe vehicle now, if it will even start.
it's a 91 sorry thought I said that.I don't have a code reader, I do have a digital multimeter but can't determine exactly where the EEC plug is to try, and the proceedure specifies a analog one for some reason. I had unplugged the battery this winter so any codes that WERE in there are probably lost.
Okay here's an update What I've done so far.
Th IAC valve...I had originally misidentified this critter. It's not a solenoid, it's the IAC valve. And it''s new ( I had mentioned the previous owner had had similar issues witht he van right?) Anyway I took it apart, cleaned it with some carb cleaner. It was a little black inside but not too bad, cleaned up well.
The wires are new
The plugs are allnew
New air filter
New fuel filter.
I cleaned the PVC valve which seemed to work fine anyway and properly put it back ( It HAD been hanging out of the hole)
The MAP sensor....hmmmmm. Well. It's got oil all over it. The previous owner DID mention a bad leak at one point that sprayed oil everywhere. Not much I can do with it ut if it needs replacing how can I tell?
the MAF sensor... Took this out. It looked CLEAN CLEAN but I carefully cleaned the filements anyway.
Result: VAN runs like crap still, wont even idle really at this point. It MIGHT now be out of fuel so I'm going to get a few dollars ina jerry can and see if it will start. It did start but still was running awful. Now it wont at all.
Just a thought but since the pcv valve was out of it's hole, maybe could bad rings and blowby be causing all of this. And have you run a comression test?
I don't have the equippment or knowledge to run a compession test.It's possible blowby could be the cause, but it's never really backfired...just run horribly and I would think I would have heard it. How do you do it and what's needed? At this point it's parked in my driveway and driving it anywhere for a diagnosis is out of the question even if I could afford it.
This should work and be fairly cheap as far as equipment. http://www.harborfreight.com/cpi/cta...emnumber=39224
(someone let me know if I'm not allowed to do that on this site)
get the tool then disconnect the ignition remove the spark plugs and thread the tester into a spark plug hole and crank the engine a few revolutions. write down the reading for that cylinder and repeat untill all cylinders are done. If any cylinders are 20% lower than the rest of them squirt a little motor oil into the cylinder and repeat, if compression increases dramaticly the rings are bad, if not you have a head gasket or valve problem.
"it just kinda sits in the hole with nothing to hold it in place"
The PCV valve should have a rubber grommet that it fits into within the valve cover. It must fit snug, otherwise you will have idling problems. There will be way too much unmetered air going into the intake manifold and it will run like crap. Be sure to check over all your vacuum hoses and make sure they are all contected and intact. They allow the same thing if their cracked or not connected.
To test TPS, set your meter to measure resistance, probe contacts (experiment, there are only 3) and move the butterfly valve (i.e. manually move throttle). resistance should change over a range. if there are breaks or flats spots (i.e. meter jumps around - nonlinear resistance), it's bad.
To test IAC, unplug it while the engine is running, if the idle does not change whatsoever, it's most likely bad.
Unplug vacuum line to EGR valve, check for idle improvement. If it improves, the EVR is pulling vacuum on the EGR valve when it shouldn't. The EGR valve should be fully closed at idle. One of two things then, the EVR is bad, or the DPFE is bad. DPFE measures the flow through the upstream EGR tube. It "tells" the EVR how much to open to EGR. Either the DPFE is bad or the EVR is bad.
To test EGR valve, remove vacuum line that comes from EVR. Place length of vacuum line where EVR vacuum line used to go. Suck vacuum line attached to EGR valve. Engine should want to stall. If that's the case, it's good. If not, either the EGR diaphragm is ruptured, or the orifice to the intake manifold is clogged. If it doesn't hold vacuum, it's the diaphragm. If it does and you can hear it open and snap shut, the orifice is clogged and must be manually cleaned by removing the EGR valve.
The stalling may be indicative of failing fuel pump, be sure to check pressure. It should be between 30 - 45 psi, KOEO. If it's too high your FPR is most likely bad. Also, see if it holds pressure when the key is turned off. If it loses pressure, it's most likely your FPR. Another sign of a failing FPR is black smoke (rich). If it's low, it causes problem too.
Finally, check your plugs again. Make sure they are all sound. Look for color/condition.
I'll try some of that later today. I really cant afford to buy any tools ( ie compression test tool) however I may be able to borrow one, have a neibour a couple doors down who is actually a mechanic , he's been somewhat less than helpful but may have a meter I can borrow.Anyway it's going to be warm today and I'll be home this afternoon so I can try some of this then.
One question, where exactly is the EGRon my 91 4.0 litre? I used to know what they looked like on an old topaz I had, but no idea on this thing.
Mine turned out to be the catalytic convertor was clogged, there are two. You might try looking into that.
Badly plugged Cat convertor usually causes drastic loss of power & acceleration. Generally idle is not affected until it's completely plugged. Feel the exhaust pressure, is it normal ?
I would check fuel pump & FPR first, most sensors can be overridden by the computer & the engine will still run. You need to get codes, OBD1 code reader is cheap ,or read one of the sticky's to find out how. You need an analogue MM because it will show the needle sweeps ,which you cant see with a digital!
Aeroman
__________________
Green-96, XLT 2wd, 3L Vulcan, from Ontario, Canada
All original powertrain except alternator & starter motor. 320,000 kms & going strong !
When describing the 96 Vulcan engine, the word Bullet proof is not too much of an exageration !!! Just a little TLC goes a LONG way.
Mine turned out to be the catalytic convertor was clogged, there are two. You might try looking into that.
You do realize you're responded to a post dated 4-29-04? He has either already fixed it or moved on to something else.
__________________ 1994 Extended Black Sport 4.0 2 wheel drive 1994 Extended Blue/gold 4.0 Eddie Bauer 4 whl-drive 1993 Extended Blue/gold 4.0 Eddie Bauer 4 whl-drive 1992 Shorty Blue 3.0 2 wheel drive +1989 Extended Red 3.0 2 wheel drive ="5ive"Aerostar'sP-R-I-C-E-L-E-S-S signed B O Z
Its funny that once again someone immediately jumps to clogged cats. Clogged cats are a result of running poorly, not the cause. The cats plug up or melt down when the vehicle runs rich or misfires or has a bad oil consumption problem or a blown head gasket.
The fuel pump is far more likely. And yes, why was this revived?
Bear River--you replied about clogged cats. And yes, why was this revived?
My answer------Cats have nine lives right? Cat was clogged? Five years ago? well, the answer is that the system has 5 more lives since this happened in 04
__________________ 1994 Extended Black Sport 4.0 2 wheel drive 1994 Extended Blue/gold 4.0 Eddie Bauer 4 whl-drive 1993 Extended Blue/gold 4.0 Eddie Bauer 4 whl-drive 1992 Shorty Blue 3.0 2 wheel drive +1989 Extended Red 3.0 2 wheel drive ="5ive"Aerostar'sP-R-I-C-E-L-E-S-S signed B O Z
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.
aerostar 4.0 litre runs horrible
