new here 3100 questions

[tractorman]

The fact that you can drive it with the TPS disconnected doesn't really mean anything. It'll be in open loop, get piss-poor mileage, and have an active code, but it SHOULD still drive fine with the TPS disconnected.

I did some searches and reading up around this site on the "quad drivers"... looks like it's basically an output from the ECM- I don't know for a fact that one of the "quad drivers" drives the ignition system, but it seems entirely possible. I'd still be looking at other ignition problems first, though. Have you replaced basic stuff like plugs and wires?

[pontiac3100]

oh yea...when i first got her.
this seemed to happen when i changed the t-stat.
but i know that has nothing to do with it.

i can't even find that damn link where you can test the icm with a dvom...

[bszopi]

http://60degreev6.com/showthread.php?t=34894

[pontiac3100]

thanks...but thats to test the coils.
and those are fine.
there was a thread where it had a layout of the icm and what the ohms should be and such.

[pontiac3100]

okay i was looking in my service book.

and i seen the sction of what sparkplugs to use.

now it went 3.1v6 had the a/c delco # and **
then skips my year.
goes to 95 3100 had a different delco # but no **
then 96 and up had 3100 different delco# and **

here's where it gets intresting.

the ** means to use delco platinum(msp?)

and i went off thinking i have a 3.1sfi...not the 3100sfi

the 3.1 uses plat. plugs too.
only year that does'nt do plat. plugs is 95...and i don't have a 95 and the plug number is the ones i have in my engine...and they're not platium either.

the 3.1 and 96+ # are different....could this be the reason.
is it possible i've fouled out the non-platium sparkplugs??

[pontiac3100]

okay i put in some ac rapidfires...still the same thing.

here's a lil update.
sometimes my heater don't work in the morning. so i get out, open hood, tap the motor and all is well.

well one time a couple weeks it was cold out...and i did'nt wanna get out.
so i hit the area where the blower whould be.
and on the 3rd hit ,the car shut off.

so i tried to crank her...no work.
then i noticed my ses light was'nt on.
so i turned her off and turn key on and tried to start...i did this twice.
nothing.
something told me to hit the dash and i did, the ses and trac light comes on.
started her up and she ran.

anther incident was a couple days ago.
i dissconnected the egr harness.
drove like that 1/2 the day....no ses light.

now i read somewhere that one of the qdm's control the egr valve functions.
so i know it does'nt know when the car is missfiring, and it does'nt keep tabs on the egr either.

tomarrow i'm going to the j/y and get some coils.

btw,
whats the signs of a bad pcm??

[tractorman]

You've just described symptoms of either a bad ecm or bad connections at it. First of all- WHERE is the ecm on these cars? I've seen it under the dash on some vehicles, and behind the kick panel on some.

I say find the ECM, tap around on it and pull on the connectors (all while the engine is running). If the engine shuts off or the ecm sets a code, then you've found a problem.

[pontiac3100]

long a$$ story:

i took the highway to work..since it was acting up i figured the pcm should know what was going on...i could'nt get past 70MPH
and when ever the t/c locked the engine would bogg down..oh man it was bad.

brought her in the shop when we wer'nt working on other cars i would work on her.

tested the injectors...all at 12.4 ohms 'cept for 1 : 12.6ohms.

here's what yall gonna find intresting.
i now have the egr and HO2 sensor dissconnected...and no ses light.
the vac lines are fine.
i removed the line to the map and the the car kept running.
ten i removed the Ho2 sensor...still kept running.
then the tps the car then missed and started revving to 2k.

so i connected the map sensor back...left the o2 sensor off.
started to test the tps sensor....and according to the chiltons....this tps has taken a dump...well to our eyes yes but to the pcm...nope.

the only thing i got was 4.9 dc volts.
at all revs.
so me and my guys were clueless onto how when i remove the harness the ses light comes on.
but it's not on when connected.
and i made sure i did everything right...even my friend also.

so then i proceed to check the pcm.
i remove glove box,the "hush" panels...and the wonderful world of gm was exposed.
so there was this big blue connector i moved it to see what other wires goes into the pcm...and the car shuts off?!
there was one that was loose and i pushed it in.

started her back up. put the glove box back together, but left the hush panel off since i'ma get a pcm.

went to park her.
and guess what...no bogging at low speeds. did belive it so i drove like "normal" no bogging
but that hot mess is still at the higher rpms.

could this still be a bad ecm...please help me??

[PCGUY112887]

+1 points for most unique problem I've ever seen on here

[tractorman]

You've got a bad connection in or near that big blue connector. You need to disconnect it and look all the pins over real close. A pin can be spread and not making good contact where the other end slides into it... or a wire can be loose where the pin crimps onto it... or a pin can be pushed back into the connector and not making good contact... or a pin can be burnt and have a bad connection.

I see this kind of thing fairly often in heavy equipment- and this sort of problem can kick your ass even if you've plenty of experience. The fact that the car died when you moved that connector pretty much proved that you've got a bad connection- now you've got to figure out exactly why. Pulling on connectors and/or wiring harnesses is one of my favorite techniques for finding bad connections, and I'd say you've done well so far.

[tractorman]

If the big blue connector is near the ECM, then don't rule out the ECM just yet- they can get bad connections inside just the same as anything else. I changed many a Cummins ECM a few years back because they sent out a run of them with bad solder joints inside. Also, check the ECM pins and the pins in the connector. Good luck and GAWDSPEED.

[Azrael]

The blue connector involves the PCM's ground (2 seperate wires), ignition feed, cruise status, all injector drivers, knock sensor, crankshaft position, camshaft position (low and high 3x), ignition control, ignition control bypass, and the iat sensor.

[pontiac3100]

damn!
thats excluding the 3 on the pcm itself. i check the connectors on the harness...it's fine.

but guess what.
i've been running errands, she did good.
then what happens...pop the "ses" light come on.

drove normal, got home parked ,shut off, started her back up.
there was that revving up and down but it was like 1,100-900rpms then corrected itself i guess.
drove for about 10 minutes and the light comes back on.

let her cool off and drove for awhile and the light did'nt come on.
so i'll hook the scanner up and see's what she gives out.

actully i think it's not advancing the timing like it should.
remember when i posted that the timing was more advanced on the low-end than the high-end??
that could be something.

[pontiac3100]

okay i went and got two tps sensors and a pcm.
but...yall gonna laugh, there's no ga 3100's that had the pcm, there was one but it had high miles and the pass side was hit...so no go.

but i got it out of a buick skylark 3100, no maf.
i was gonna get the pcm out of a grand prix se 3100...but they had it mounted on the outside...so i did'nt trust that.

will the buick pcm work with my car??

[Azrael]

The skylark is an n-body like the grand am so if the year was a 94-95 then it should work. But double check the part number between yours and the buick one to be sure. It'll be on a sticker on the PCMs.