TAChad

I installed a cam, injectors, TB, and a few other things on a friends car 97 trans am. The pcm what programmed for pcmforless....basically the car ran great for a few days but now it takes a lot of cranking to get it started up, when it idles it surges in RPM, and when you go to give it some throttle the RPMS wont raise hardly at all and it starts to spit and sputter. it ran great, then It started doing this all of a sudden. The cheap auto zone scanner said that it had a p0100 code, but i dont know if this was a previous code or not. I did a search and im going to check the pink wire on the MAF harness for 12 volts, but are there any other suggestions? I checked everything i know of. I am just wondering if a MAF would cause this prolem or not because i thought the computer would just go into open loop and run poorly....but this car wont drive, just surge while idling. Thanks

Chad

IllusionalTA

iF you flashed the pcm it woudln't have any stored codes'.. i'm not familiar w/ the OBD II Diag. Code's.. SO look into what she's telling ya.. OTherwise i'd look into that GD opti

turbo_Z

You could try cleaning the elements in the sensor to see if that does anything positive for the situation.

Something else you can try is to unplug the MAF and running the car that way. This puts the PCM into speed density mode which is basically where the computer combines a few sensor inputs to calculate incoming air as opposed to the MAF sensor which measures air directly. If the MAF was causing those problems you described then they will disappear if the sensor is unplugged. Only problem is the car fans will run constanly and throw all the MAF codes but at least you will have an good idea what the culprit is.

BAD 97 WS-6

The easiest thing to do is to swap with another MAF and see wat happens. I just put my motor back in this week. The car ran like crap. After changing 02's and the problem still occurring, I swapped MAFs. Problem solved.

TAChad

Thanks for the suggestions guys. I'll unhook the MAF and see what happens. I told him it seemed like the opti went out on him being how he described it ran like crap all of a sudden and how it sounds now. Its nearing 80,000 miles and i just had the opti off sitting around for a week, so maybe it it got some moisture in it and fried. Thanks

Chad

HBHRacing

yes a MAF can do that. it can cause a feeling of low fuel volume IE the sputtering. I would try unhooking the batery and seing if the code comes back. you can always try cleaning the MAF and unpluging it

TAChad

ok, im running out of ideas. I have tried unplugging the MAF...no difference. I tried swapping the MAF with my own... no change. I tested teh pink wire for 12 Volts and there wasnt any voltage on the pink wire going to the MAF plug so i just used a wire straight off the battery and tapped into the pink wire from the MAF plug and still has the same problems.
--Are there any other reasons i wouldnt have 12 volts to the MAF?? would a bad opti have antyhing to do with that?
--the symptoms are wierd, you can crank and crank on the starter and it'll just sputter, but if you let off for a second then try to crank again, it'll start right up like nothings wrong for a second, but it'll just die and wont rev up at all.
--The only codes i am getting are the p0100, but i know that sometimes when an opti goes out it wont throw a code...they way this thing is acting, it seems like an opti, but i just am curious to why it has a MAF code and no voltage to the pink wire on the MAF connector.
Any suggestions or ideas i can try? Thanks

Chad

meangrn94ta

i'm just pissing in the wind here but after i did my cam swap it has a high rpm stubble and everyone said opti and coil, check plug wires and none of these were problems. but i have heard that if u have plugs wires cross it will throw and O2 code about miss firing. maybe that is what that code is. check the plug wires. oh and if u have any suggestions of why i would have a high rpm stubble let me know.

TAChad

I triple checked allt eh wires when i put them on...not to say that they still couldnt be crossed, it has happened to me before, but the car ran GREAT for 3 days after the mods were put on it, thats what is confusing me.

Revenant

Im having the exact same problem with mine. The only difference is mine's running fine except for the loss in mileage (21mpg to 17mpg). And whenever i delete the code i have the same problem starting mine and it kicks the code right back at me. I've tried swapping the MAF, MAP, and the TPS all with no luck. Let me know if you figure it out

Injuneer

Its a little puzzling why with a direct connection from the battery you don't get +12V on the pink wire. The only way that could happen would be if there was a short in the pink wire somewhere in the harness. But I would think if you had an existing short in the pink wire, it would have blown the fuse to the pink wire. I guess the short would still be pulling down the voltage, but you should notice sparking or a high current/heat in your jumper from the battery.

Check the pink wire for a ground by connecting one lead to the pin in the harness connector and the other to a good ground. Should be infinite resistance, if it isn't you have a short to ground.

You also need to check the MAF fuse, since that circuit also feeds several other items. On Shoebox's 95 wiring diagram, it shows as fuse #5 in the instrument panel fuse box, 15A. 94 might be different.

TAChad

injuneer...sorry if you misunderstood what i typed, i didnt really specify very well. I didnt have 12 volts on the pink wire until i took a direct 12V source from the battery, then i had 12 volts at the pink wire on the connector....but even with the 12 volts on the MAF, it still did the same thing, there was no difference in teh way it ran. The car im working on is a 97, i have a 94 and just switched out my MAF for his and there was no difference. I didnt know there was a specific fuse for the MAF and other sensors, so i will make sure to check that fuse. One thing i did notice is that when i connected the hot wire directly from the battey, there was some currect being pulled because i could see a very little spark, but i dont think there is a short to ground or anything like that because there wasnt any heat or anything coming from the wire. Any other suggestions? thanks

Chad

TAChad

I checked the number 5 fuse in the fusebox on the side of the dash, and it was the brakelight/turn signal fuse...so i guess it differs from a 95 like shoebox's diagram said...it was good, However, on the underhood fusebox i found a blown number 10 fuse that said "Engine sensor", replaced it and it still does the same thing. I have no idea whats going on with this thing. Has anybody had a similar problem like this?

Chad

Injuneer

Did you check the fuse to make sure it didn't just blow again after you replaced it? The 97's seem to have the problem with the pink wire way more frequently than any other year. Also, when you replaced the fuse and when you powered up the MAF with direct 12V, did you reset the PCM, or at least drive it for a while to allow the long term fuel corrections to get bck where they belong?

TAChad

AFter i replaced the fuse i did make sure it didnt blow again, which it didnt...it was still good after several attempts of trying to start it. i pulled the ECM batt. fuse to reset it, and it still didnt make any difference. Id like to drive the car, but its runnign so badly, it wont even go...im thinking it seems to be one of thos wierd opti problems, but i am still unsure. any other suggestions? thanks again for everyones help

Chad