1994 transport stalls when accelerating

pontiacfanactic · #1 03-07-2008, 04:24 PM

My 1994 3.8 litre salls when accelerating from a stop. Noted some leaking of tranny fluid from cooler lines but unable to determine where it is leaking. Could this be causing the stalling of engine? Engine tach is running slightly over 1000RPMs. Should adjust idle speed or is it nonmadjustable or something else?

drift28 · #2 03-10-2008, 10:29 PM

Is the air filter secure,the carburetor is jetted to see the filter restriction.Float may be adjusted too high.

LMP · #3 03-11-2008, 01:40 PM

Quote:

Originally Posted by pontiacfanactic

My 1994 3.8 litre salls when accelerating from a stop. Engine tach is running slightly over 1000RPMs. Should adjust idle speed or is it nonmadjustable or something else?

"stalls"....does the engine stop completely or just stops accelerating properly?
If it stops, will it restart and when?
..runing over 1000 rpm...you mean, at idle?...not when it "stalls"....
IDle speed ..(as well as injectors)...: computer controlled....no external adjustment...idle air pintle self adjusts after one or two operations after replacement...
Transmission leak un related....or....did you mean the engine keeps running but transmission falls out of gear..?

so...some more detailed info needed before any hypothesis can be brought forward..

pontiacfanactic · #4 03-12-2008, 10:38 PM

Regarding if it stops or stalls it usually kills the engine when letting off the throttle and the RPMs zero out as I am in drive moving. It will happen without notice. As for the question of if it is idleing at 1000 it is and it even goes around 800-900 at times. Transmission leak seems very slow and gears seem to work fine throughout, did notice RPMS running approximately 3000 when in 4th gear or overdrive also cruise control will not engage when attempted, could this be related as well. Also has problem with alternator occassionally running at 9 volts and then will return to 14 volts on its own minutes later very frustrating. Any ideas? Thought I read in another thread something about a sensor would kill engine if faulty, throttle speed?

LMP · #5 03-13-2008, 07:31 AM

Yes your symptoms read same as another thread and involve Throttle Position Sensor, a common failure.
http://www.automotiveforums.com/vbul...d.php?t=892700
Check for that before anything else. At that age, it would be "normal".

AND..obviously you have another problem with the charging circuit. One similar case recently was about the connection post on starter..so check for that first as this is "free"...but consided you might need an alternator, or replacing the internal diode pack and/or regulator.
http://www.automotiveforums.com/vbul...d.php?t=886084

pontiacfanactic · #6 03-15-2008, 10:31 PM

Your were right about the charging circuit problem. The alternator did the same problem as before no charging on ampmeter, would stay around 10-8 volts. Removed it and had it tested. Guess what, it failed and so was replaced with a life time warranty one, thus far has not stalled but does not have cruise control yet and never did have a CE light on. Would the throttle sensor be bad without flipping the light on? Or do you have any other ideas what could cause cruise not to work i.e. fuse ,wire ,vacuum hose, other cause? Please respond and thanks for the replies.

LMP · #7 03-16-2008, 08:11 AM

...what about the other symptoms...running in 3rd only, (3000 rpm at 60mph).
Failed TPS inhibits 4th, OD and cruise...but it comes with a code...
If only cruise is inoperative, it can be for a misadjusted/failed brake switch, disconnected vacuum hose to cruise bellows...will check for more, but report on other symptoms.
..in fact, will the CEL test ON when you first turn the key to ON?
..and your initial stalling problem is relevant of the operation at 8-10 volts. SHould be OK now.

pontiacfanactic · #8 03-23-2008, 10:43 PM

I must admit you were right from the start LMP it turned out to be throttle sensor and I had it replaced at my brother in laws garage. The pontiac runs fine and I never new it had that much acceleration almost as good as my 95 that I put Lucas oil in the crankcase and put a new map and maf in. Everything returned to normal including the cruise and the stalling quit. I bet I will even get better MPG until we get another political party in charge of petroleum.

Thanks again and this is proabably the only forum that is beneficial to people

POST REPLY TO THIS THREAD