93 j30 stalling while driving

[jntsnider]

i have had my j30 for about 4 months now. about a week ago i was driving along at about 45 mph or so, and it started to hesitate. i gave it some gas and it seamed to quit. i drove it again the next day and it did the same thing. i had a mechanic come to the house and test the electronics. the air flow was low. i replaced the air filter, cleaned the throttle body and it did not have bad reading on test. drove the car and it actually stalled while going about 45 mph. i replaced the fuel filter and cleaned the throttle body again. ran good for a day then stalled on me again. every time this happened the car started right back up. but this last time it stalled while cruising , when i tried to restart the whole car shook while i tried to keep engine going. it finally smoothed out and stalled again before i got home. any ideas before i waste money.

Modified by jntsnider at 4:32 PM 7/14/2009
Modified by jntsnider at 1:22 PM 7/17/2009

[alex61089]

I had a problem similar to this. My car would stall out and turn right back on with no problems. only i didn't stall at those speeds it only seemed to occur when i was waiting at a light (foot on brake) I finally found out that it was my MASS AIR FLOW SENSOR or MAF I would take it out and clean it with some MAF cleaner. You can get it at Auto zone or pep boys for about 8 dollars and spray the screen, and connectors with it. See if that works before you decide you might need a new one. I believe it is the CRC brand. (the cleaner)

[yodawill2000]

any ZERO RESIDUE contact cleaner will work.I clean mine twice a year along with the air filter replacement.

[jntsnider]

i cleaned the maf and adjusted the idle speed. after looking through the manual, i figured that my idle speed while in nuetral was around 1150 rpm's. i adjusted it down to around 670 as manual reports. it does not idle so high now. and it feels much different while sitting at light or stop sign. before when the idle was high, the engine would bog down alot while applying the brake. now it barely makes a difference while applying brake. i had taken it for a test drive and it feels great but it always started to feel great. then out of no where it would stall while driving at speeds. i will need to drive it more to decide if the problem is fixed. thank you for the tips alex and yoda.

93 j30 160,000 dark green and smooth. Modified by jntsnider at 2:07 PM 7/19/2009
Modified by jntsnider at 2:09 PM 7/19/2009

[yodawill2000]

Good Job !!

Keep us posted.

[jntsnider]

took it for a real long test drive yesterday. drove for about an hour. shutting it off a few times in the proccess. it ran great. like a new car. i am glad i did not get rid of it..

[alex61089]

I'm really glad to hear that; I hope all goes well for you; If you ever have any problems you know where we are at

[jntsnider]

thanks for all the hospitality, i will always check here before i do something drastic with my car. i can't find anyone around here in jacksonville who has a j30 to compare notes with.. this forum rocks.. as a second job, i deliver pizza a few days a week. to give it a true test, i drove it to work last night. it ran like a champ.

does anyone know where the electrical system is usually grounded? when i turn my headlights on the dash lights don't work. it even makes the radio and a/c lights go out. my dad told me he had the same problem and that is what was wrong with his.. any ideas will help.. thanks.
Modified by jntsnider at 2:27 PM 7/22/2009

[yodawill2000]

Give the dimmer on the left of the dash a good smack. (Left of steering wheel)If that brings the lights back there's a cold solder joint on the dimmer switch.VERY common on the J's.

[alex61089]

Yeah mine does it here and there and I start getting paranoid until I realize all I have to do is smack it and Bam! it works every time . Definitely the easiest fix I've done on the J yet lol.

[jntsnider]

i tried the smacking thing last night. i hit it different ways and harder each time, but it did no good. the dash lights still don't come on. and i still loose the a/c display and radio display. need to check for loose ground connection. any ideas where that could be???

[jntsnider]

ok now, after a week of driving my j for heavy travel around the city with no problems, it stalled on me twice yesterday.wtf it first did it at a red light. when light turned green, i let off the brake and just touched the accelerator and it died. restarted fine. later on it stalled again when i was coasting , coming to a stop.. started back up fine.. no more problems the rest of my trip around town. this has me confussed... i am laid off and can't afford to keep going through this.. about ready to sell this j 30.. help before i start placing ads to sell.

[GerryO]

Clean the throttle bodies and check the TPS output voltage?

Clean the IAC/AAC valves and adjust the idle speed screw per the FSM instructions with the IAC disconnected?

[yodawill2000]

Yeah ,, What he said. hehe

GerryDid you ever get the consult working ?

[jntsnider]

i have already cleaned the throttle bodies and already cleaned maf. i replaced the air filter, fuel filter. and adjusted the idle to 670 per manual. the rpm's do not bounce around at any time, not even when it starts acting up. it sits steady all the time. do you think the maf is bad if i cleaned it a week ago and it starts this again? i also noticed that the fuel pump makes a noise that is very noticable from time to time could this be signs of pump going bad?

[yodawill2000]

Yes.Ive heard they sound like a hive of bee's when they are going out.Running the tank near empty will speed up the pump failure.As GerryO asked, have you adjusted the TPS yet ??(Throttle position sensor)

[jntsnider]

i have not had time yet,, i have a two year old and wife works during the day. i work part time in evenings. but i will look into it as soon as i get time. like later this week.

[yodawill2000]

Roger that.FYI its a quick adjustment.

[GerryO]

GerryDid you ever get the consult working ?

Well.....not yet. First I need to find and re-intall that length of tubing that heats the AAC valve, lowering the idle speed while the car is moving and as the engine warms up. The car has been parked a while. My wife did drive it last weekend.

Way too many summer projects and I want to find a '96/'97 plenum complete with the PCV valves mounted on top.

[GerryO]

i have already cleaned the throttle bodies and already cleaned maf. i replaced the air filter, fuel filter. and adjusted the idle to 670 per manual. the rpm's do not bounce around at any time, not even when it starts acting up. it sits steady all the time. do you think the maf is bad if i cleaned it a week ago and it starts this again? i also noticed that the fuel pump makes a noise that is very noticable from time to time could this be signs of pump going bad?

Check for vacuum or intake system leaks too. Air entering the plenum could be by-passing the MAF.

Make sure that the throttle plates move freely, always closing to the same point, making for a consistent TPS output voltage reading.

Fortunately (for me) I haven't experienced any fuel pump problems.

What does the FSM suggest?

[jntsnider]

i tried to do all the things you mentioned and i think something worked. at least at this point it runs good.

[GerryO]

i tried to do all the things you mentioned and i think something worked. at least at this point it runs good.

Nice work and thank you for the good news!

Any educated guesses as to specifically what made the difference?

[jntsnider]

well after about 2 weeks now of running great , it started stalling again. this time it only seems to do it when it is raining really hard and there is standing water in the roads. i think it could be moisture getting on wiring, but at this point i am still totally baffled.

[GerryO]

well after about 2 weeks now of running great , it started stalling again. this time it only seems to do it when it is raining really hard and there is standing water in the roads. i think it could be moisture getting on wiring, but at this point i am still totally baffled.

As I go through things on my J, I'm checking and applying dielectric grease to all of the connectors (but NOT those of the O2 sensors). In addition to preventing corrosion, it provides a bit of water proofing protection too.