My 86 Cougar GS (that I bought new in 86) starts right up but immediately stalls unless I keep my foot on the gas pedal. This started about a month ago with the engine surging for a while at start up but then it leveled out after a few minutes of running. Now it just starts right up & stalls. Clogged fuel injector? Any ideas on how to fix this would be appreciated!
Is it throwing any codes?
I don't know and need to find out. The car has 135,000 miles on it. Do you think it could have a timing chain issue?
Highly doubtful. TPS or ISC are my first thoughts, but get the KOEO and KOER codes to give you some better direction.
Unfortunately I don't have any diagnostic tools. If the problem is something to do with the throttle body will that be expensive to fix?
You only need a paper clip.
Probably a test light or multimeter too.
http://www.thorssell.net/hbook/eectest.html
Let us know what you get for codes.
Will do. Thanks all for the great advice!
I used to use a 12v computer speaker, made the same beep as the cheap code readers back in the day. Ive also soldered a tail light bulb to wires before, just about anything will work.
Thanks! BTW, people have told me the stock 3.8L V6 in my 86 Cougar is the worst engine Ford ever made. Even worse than the Chevy 305 V8. However, according to Wikipedia the Ford Esshag 3.8 L V6 is a pretty good engine. Do you think the Esshag was a bad design from the beginning?
83-87 3.8 V6 = slow turd
88+ 3.8 V6 = slow, head gasket blowing, turd
What is the ISC? I've replaced the TPS, the fuel filter, the fuel regulator and the fuel injectors. There are no vacuum leaks and the car does retain fuel pressure after being shut off (35 lbs). However, the fuel injectors aren't always firing at idle so the car always stalls unless I pour gas down into the TBI or spray some carburetor cleaner down there (car runs great for a few seconds if I manually feed the TBI gas). Could it be the pick up coil? Or maybe the module on the distributor? Also, we used a paper clip to get engine codes and it indicated the TPS was the problem - but the the new TPS hasn't made any difference. Any advice would be appreciated!
My guess is that was a typo for iac, idle air controler.
If you are loosing spark, it will stop firing the injectors.
Try unplugging the spout connector. If that makes no difference, then it is time to replace either the pip in the distributor, or the tfi module. I usually swap both, if one fails it seems like the other follows shortly after.
Edit
The pip is what tells the computer that the engine is turning over. This signal fires the injectors after being modified by the tfi module. Unplugging the spout might rule out a computer problem, it will put the computer in "limp mode", bypassing all but the necessary sensors to limp the car to a dealership.
The tps should sit around 1v at idle and reach 3.5v higher then idle voltage to initiate a full sweep. Everytime the computer is powered on, it checks for idle voltage. Anything between about .67-1.19 volts whould be in range, optimally closer to the middle of those numbers. Check for a constant raised signal until it pegs or reaches at least 3.5v higher then idle voltage. Any dead spots or higher then 5v indicates a bad sensor or possible ground wire.
Compared to Ford's 3.8, the 305 was a Crown Jewell... Other than being a turd(mostly due to emission control/tuning), really no different than any other small block Chevy... Ford's 302/5.0 in same era didn't run much if any better...
The only real problem with Ford's 3.8 were the heads... Aluminum heads were still in their early stages and Ford didn't allow enough material between the fire rings and some of the oil & coolant passages... So unless one flushed cooling system almost yearly they blew gaskets with regularity(I honestly dunno if that would have saved them)... The sharp 90* transition machined from lower head bolt surface to vertical was pr0ne to cracking in the early heads... To put it this way, in the last 50+ years I've owned close to 200 cars, not one had a Ford 3.8... Yes I've owned a 305 or two even some Chevy & Buick 3.8...
Haystack, Thanks for the detailed advice. It's greatly appreciated! BTW, what is the PIP?
Thanks for the background info on the 3.8L & the Chevy 305. Aren't the 3.8L engines in the 1989 Fords and newer more likely to blow a head gasket than the Fox body Cougars & T-Birds?
Pip is the pick up in the distributor. Can't remeber the more common name for it, but its similar to a crank or cam position sensor in a more modern engine. It is under the rotor in the distributor, and you may be better off buying a whole new distributor if you can get one.
Thanks for the additional info. I think the distributor is original but there's only 135K miles on it. I am guessing a new distributor will be quite expensive.
A brand NEW dist for my '96 F-150 with 5.0 was like $125... My old one has a bad PIP but I was too lazy to change it out... Of course it has remote mounted module, if that's included on new dist you can probably add $40-$50...
Is the idle air controller the same as the PIP or the TFI module or is it a separate part? And where is the "spout" I should disconnect? Is it the TFI?
Spout connector is a jumper plug near the distributor. It basically turns off certain computer functions and puts the car in limp mode. It is usually near the tfi plug that goes into the bottom of the distributor.
The tfi mounts to the distributor and the large plug goes in there.
The iac isn't the problem, forget about that for now.
No basically it prevents control of timing advance by ECM, AFAIK everything else functions as normal... Definitely does not activate limp mode... Limp mode sets injector pulse at a fixed state, sooo engine is too rich at idle(usually see wisps of black smoke), too lean cruise, performance is in toilet...
I had to look it up myself to make sure I wasn't forgetting things. Getting old!
(https://www.nmr.mgh.harvard.edu/~reese/MegaSquirtArticle/CFI%20ISC%202.jpg)
ISC = Idle Speed Control. CFI's method to control idle. It physically moves the throttle blade to adjust airflow. IAC sends air through it and bypasses the throttle blades.
This...
You didn't indicate what the actual code that was thrown... Have you verified voltage at idle?
Although the 3.8 likes to blow head gaskets, the earlier ones aren't nearly as bad as the latter. Mine made it 226k before blowing.
Really? Thats interesting, i had problems a few times where the car wouldnt even start but if i pulled the spout it fired right up. I think this was on my 87 tbird with a 302, pulled off the timing chain cover and the timing chain was so loose you could almost touch the chain together inbetween. After i swapped the chain with a cheap double roller that issue went away. That really, really would explain alot.
I would do some more trouble shooting before I would replace anymore parts.
If you are still getting a TPS error code, that needs to be figured out.
List the KOEO codes you get and define whether they are hard codes or memory codes.