[V8] Three codes

[dsaad@icehouse.net]

I did not see an O2 sensor in there anywhere. A internally shorted O2 sensor can
cause some wierd behaviour. BTDT.

I would also look hard at the ignition system. Are there any carbon tracks or
cracked or dirty parts? You may have to pull the dist caps off for a good look.

The TPS has no function on a 5-speed, but the idle and WOT switches have to be
working. You could have a problem there. You have to check the mechanical
alignment of the switch as well as the electrical function.
To accurately test the switch function in-circuit you are going to have to probe
the wires at the back of the connector shell (the side the wires go in) or at
the ECU terminals. Probing at the ECU is the best test because this is what the
ECU actually sees, and accounts for any wiring or connection problems.
Be aware that MANY intermittant electrical problems are caused by improperly
probing connectors. Be careful not to bend contacts in any way.
Never cut or pierce wire insulation to make a measurement - unless you want to
have future intermittant problems...
Also look for corrosion inside the connectors. Many of these connectors can be
disassembled and individual pins removed/replaced.

Dave

Quoting "Coleman, David" <David.Coleman at blackrock.com>:

> Hello All,
>
> Before I go mad w/ various part swaps, I wonder if anyone has any
> advice:
>
> My '91 5-speed has an AudiConnection 4.2 installed with the original
> unmodified 3.6 ECU -- a combination known to work with no problems
> whatsoever.  But since the install I've had a couple symptoms that occur
> sporadically, typically a rough stumbling w/ general lack of power under
> load at low rpms, and seems to clear up once past 3.5k or so.   Other
> times it will barely run, engine idle fluctuating violently, and when
> trying to get underway, protests by bucking and snorting, making any
> forward progress nigh impossible.
>
> In both/all cases, the engine seems to run quite rich.  Stinks to high
> heaven, and the tailpipe is very sooty black.  When it's in full protest
> mode, I smell raw gas while cranking, which will flood the sucker out.
> Here's how things have gone down, code-pulling-wise, over the past 50
> miles:
>
> 1)  Car runs pretty well, except under low rpm load where it sputters
> and farts --  Code:  2111 (ECU) was only code.  Replaced plugs, FPR, air
> cleaner, checked vent hoses.  Runs pert near flawless for 5-10 miles
> until low-load symptoms creep back into picture.  Gradually gets worse
> across wider RPM range until:
>
> 2)  Car in full protest mode, barely runs and is essentially undriveable
> -- Code:  2413 ("Mixture problem, runs rich or lean, vacuum leak"). .
> No crap.   Tap ISV w/ wrench, clean contacts on TPS, eyeball vent hoses
> again.  Now no start, strong fuel odor points to obvious flooding.  Pull
> back spark wires and starts up, same nasty running condition.  Pull code
> again: 2413 is gone, replaced by 2213 (ISV).   Shut down, restart, try
> to clear its throat a bit, code back to 2413.
>
> I have a 3.6 TPS I can swap on, a spare ISV of unknown condition, and a
> spare MAF sensor of unknown condition.   I can swap the parts to see
> what happens, but wonder if I should be looking at new plug wires, caps,
> etc.?   Did I miss a bad hose?  Any thoughts are welcome, otherwise I'll
> post results from parts swapping.
>
> DaveC.
>
>
>
>
>
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