bad computer?


LyndsiK
12-06-2006, 03:18 PM
how will my car act if my computer is bad/malfunctioning? or will there be many different scenarios depending on whats wrong? thanks

MT-2500
12-06-2006, 03:49 PM
how will my car act if my computer is bad/malfunctioning? or will there be many different scenarios depending on whats wrong? thanks

Well we would have to right a book to tell it all.
But it will do one of two things on bad days . Quit running or act up.
And then on a good day it may not act up. m:grinyes: :grinno: :lol:

But to better help you.
We would need more info like.

Tips on getting a good answer to your questions.
People trying to answer your question do not have a crystal ball.
So give them all of the info you have like year make and model and engine and transmission and mileage.
Also cars engine and transmission service history or any recent repairs or problems.
Also a description of your problem and what it is doing or not doing.
If you have codes give up the code no.
And remember a code does not say replace the part but only points to the problem that you have to check out.
So to better help you give up all of the info you have on it.
MT

LyndsiK
12-06-2006, 04:21 PM
97 gtp, 160k..........its just been throwin codes left and right, seems like every day its something different and when thats fixed, it never actually fixes the problem...... so i was really just throwin ideas out there, that maybe the pcm malfunctioning might cause a bunch of bogus problems.
things like, one night it said cylinder 6 misfire, checked it, sparked, clean etc, next night it said cylinder 2! that one seems fine as well. has new plugs and wires. vacuum leak somewhere, you can hear it, it runs like sh*t, but nobody can find it! ive taken it to two diff garages three times....O2 sensor, egr valve, throttle body position sensor, thermostat, supercharger gasket, coupler, head gaskets (all the others in between) have all been replaced. and then i was told that the throttle body gasket was the cause of losing coolant....well that didnt take of that problem either! im at my wits end! i know the comp wouldnt be the cause of the coolant leak (temp never rises, no visible leakage and the oil seems fine) but maybe all the other problems? currently its running so horridly that im scared to drive it! something's missing, we have NO POWER to even get up to speed, i feel like im gonna get run off the road!

BNaylor
12-06-2006, 04:27 PM
There are many but we would just be speculating.

One such scenario is the problem you are having with the fuel injection system DTCs. P1200. It is a fuel injection system electrical control problem.

http://www.automotiveforums.com/vbulletin/showthread.php?t=651142

Another scenario is the 12 volt PCM sense fuse pops due to a wiring or internal short in the PCM module but I doubt this is your problem. The car would not start.

The PCM module will normally give off DTCs if it is an internal problem such as low voltage, loss of serial data, a cpu error or any of the output drivers. If you suspect the PCM module then controlled substitution may be necessary by installing a known good or replacement PCM module.

BTW - Is your GTP stock or modded?

LyndsiK
12-06-2006, 04:38 PM
no its just stock.....

BNaylor
12-06-2006, 04:49 PM
I noticed in your other thread you mentioned CAT convertor. Was an exhaust backpressure test performed or an engine vacuum test? A bad CAT will give random and inconsistent DTCs like misfire P300 or even P30X and make the PCM look questionable. With your current mileage has the CAT ever been replaced. Mine failed back at 70K miles due to misfires which were corrected but the CAT went South. The engine will run like crap.

Also, double check and see if the P1200 DTC is consistent. Have the PCM module reset.

LyndsiK
12-06-2006, 04:54 PM
yeah the last garage i took it to told me that the cat was bad...i havent had the chance to fix it yet but im SURE they didnt test it or anything, but they're also the ones who told me the throttle body gasket was bad causing the leak....which turned out to be false.
we definately were not aware that it would cause random misfires like that....im getting the part tonight so i guess hopefully that'll take care of it.
would i just have to take it in again to have the pcm reset? is that expensive usually?!

MT-2500
12-06-2006, 04:54 PM
97 gtp, 160k..........its just been throwin codes left and right, seems like every day its something different and when thats fixed, it never actually fixes the problem...... so i was really just throwin ideas out there, that maybe the pcm malfunctioning might cause a bunch of bogus problems.
things like, one night it said cylinder 6 misfire, checked it, sparked, clean etc, next night it said cylinder 2! that one seems fine as well. has new plugs and wires. vacuum leak somewhere, you can hear it, it runs like sh*t, but nobody can find it! ive taken it to two diff garages three times....O2 sensor, egr valve, throttle body position sensor, thermostat, supercharger gasket, coupler, head gaskets (all the others in between) have all been replaced. and then i was told that the throttle body gasket was the cause of losing coolant....well that didnt take of that problem either! im at my wits end! i know the comp wouldnt be the cause of the coolant leak (temp never rises, no visible leakage and the oil seems fine) but maybe all the other problems? currently its running so horridly that im scared to drive it! something's missing, we have NO POWER to even get up to speed, i feel like im gonna get run off the road!

As Bnaylor says.
You may have to use the Honda cure all fix of trying a known good PCM.
Many strange codes is one sign of a bad PCM
But first check all grounds real good.
Has any work been done around any engine/transmission grounds?
Another thing to check is pug in on pcm and or unplug it and plug it back in and also try a battery disconnect.
Let us know how it goes.
MT

BNaylor
12-06-2006, 05:08 PM
One of your problems is having to rely on what other people like mechanics tell you and your lack of DIY diagnostics equipment. Even mechanics have to go through the process of illimination. The mechanic must have run some test to determine the CAT is flaky so I would not rule it out. If the CAT is causing the misfires then it may resolve your issues. But then again uncorrected misfires may ruin yor new CAT.

If you have an Autozone around you may want to invest in an inexpensive odb-ii hand held scanner. Actron has one for around $60 which is fine for generic codes and resetting the PCM. Model CP9125. A monkey could operate it. Sometimes disconnecting the battery negative cable for a few hours may cause reset or clear history DTCs but it may not work all the time depending on how severe the DTCs are and whether they are classified as Class A.

The key to finding and fixing problems is following a systematic troubleshooting procedure but at times that is not an easy task. And never give up.

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