Hesitation....stalling...

[GNBeswick]

Hey guys, Ive been having some problems with my 85 GN as of late, and was hoping maybe someone has a solution, or knows the problem. Often times after starting the car, it hesitates rather heavily and tends to feel like it's cutting in and out. It does this unless you give it a good amount of gas, however when giving it more gas to cure the hesitation it will often not respond for a second or so, make a popping noise (an explosion I assume), and then take off. After about 3-4 minutes of driving the car is fine and drives great. Another problem that I have had, while not as frequent, is the car will start to hesitate and cut in and out while driving normally (seems to happen out of the blue) and if I do not give the car alot of gas, it will stall immediatly. While the car is cutting in and out, the service engine light flashes in and out as well. After this happens I usually just reset the computer and it works just fine. The last problem Im having, is that occasionally when I use the radio or the air conditioner, and come to a full stop, the car gives a beep and stalls. Ive tried a few things to fix these problems, but to no avail. Ive replaced every vacume line, replaced the oxygen sensor (as one of the error codes came up as the oxygen sensor), and replaced the entire computer. Im thinking it has to do with something electrical....but if thats the case, I dont know where to start to locate the problem.

 

[cool 84]

It's weird that the check engine light flashes when it has the problem. I would've said computer but you've already replaced that. Check the grounds near the AC compressor and the positive battery cable, especially down around the headers. I have Kenne Bell headers also and they make a lot of heat. I've also had the ECM power wire break internally but the insulation was ok. The car had an intermittent cutting out and then it would be ok for a while. I accidently found it when I pulled on the wire accidentally and it stretched.

Also, my first thought at the beginning of your post was coolant temp sensor since it sounds like it's running lean when cold. Maybe you have two separate problems.

One last thing, do you have a scan tool?

 

[jacksorroche]

GNAsuka,

I thought that I was the only person in the world that had this problem. I have had the same problem that you just described since I got the car. I have replaced the O2 sensor as well, however I still get the hesitation even after the car has warmed up. When I punch it, it will hesitate until about 35 mph, then it takes off like a bat out of hell.

I read a post a few days ago about setting the IAC and the TPS. I don't have a scanner, but I did try and set the TPS. I couldn't set the voltage correctly. It would set for idle, however, I couldn't get the TPS voltage high enough for WOT. I am wondering if I need to replace the TPS.

By the way, what is the best scan tool to use for our cars?

 

[turbobooster]

hey well i guess that makes 3 of us now except on my ride it takes off good and keeps going good if i take off giving alot of gas but say i take off normallly and let it pick up speed slowly not toomuch gas it hesitates alot at 25 - 30mph and will throw black smoke from my exhaust r u guys having the black smoke too? what is causing the black smoke and bucking at 25 mph ? the wierd thing it only does it at that mph sorry guys i couldnt guve u the help ur seeking im having the same problem

 

[jacksorroche]

turbobooster,

I don't have the black smoke, just all the other symptoms.

 

[turbobooster]

heys guys goodnews well can be good newa for some but bad for others i found where my problem of my car bucking hesitating at around 35-30 mph is coming from the guy who diagnosed my ride said i have a bad igniton problem thati need the whole thing (coil pack and module ) which is can be bad news becuz its not a cheap part from the research ive done. well luckily for myselfd i got the coil pack and module from an 85 GN and really cheap so im waiting for it to come and getting it installed and problem solved but i will update u guys on this segment i really recommened u get ur car diagnosed proffesionally or someone wit a scantool will tell u where the probelm is it helped me so good luck