74 replies to this topic

[Twichel04]

Your mechanic should be able to test if the coil pack is firing properly without having to buy a new one to swap it out. He should be testing and diagnosing, not throwing parts at it.

[minidaves]

problem solving always requires logic, broken wire from ecu to coil pack would do this, get the continuity tester our or the scope to check feeds and voltages and the correct info is arriving at places

[rane]

All wires were tested and are live, intact, and connected. Traced everything back and all looks to be correct.

As of just now, replacement coil pack produced the same result.

Frustrated.

Does this mean I need to start diging for an ECU?

[rane]

Finally was able to lug the car to the driveway from the mechanic after he has thrown his hands up.

Mechanic replaced the coil pack (new one still in it) and exchanged the CAS. No changes there. He also ran through diagnostics and noted CAM and CRANK faults. He cleared these and they never returned. He claims he found no broken wires and continues to believe all things point to the ECU.

I've since brought the car back to my home and went through diagnostics today.

Two faults registered today - 11 Batter voltage, logged, sensor output voltage too low and 02 coolant temperature sensor circuit, logged, voltage too high. I cleared these and they did not return.

While doing this, the engine bay started smoking and white smoke was coming out of the reservoir and there was water on the driveway. I've never noticed this before but I have never let it idle this long either.

My diagnostics ended there, but before the smoking began I obtained component data I as follow:

RPM 1354
ECT 91
IAT 49
MAP sensor 54.5
Throttle position 4.9
Throttle SW. OFF (however this read ON initially then changed to off)
Battery Volts 13.9
O2 Volts BNK 0.48
F/BACK BNK1 ST OFF (however this read ON initially then changed to off)
COIL 1 CHARG.T 1.80
COIL 2 CHARG.T 4.00
INJECTOR 2 P/W 1.64
INJECTOR 4 P/W 1.64
STEPPER POS 10
Ending RPM 1235

A very generous local SPI owner has offered to come take a look in the near future. Any ideas for when we really start getting our hands dirty? I'm hoping the overheating was a result of idling in the driveway and it not running correctly. Ideas there appreciated too...

Thanks!

Edited by rane, 14 March 2013 - 10:12 PM.

[Fast Ivan]

just to be clear - you have changed the spark leads havent you?

[rane]

Ha. Yes. I asked this as well. I have not done this myself, but supposedly things were switched around with the same effect.

[Fast Ivan]

ok.
was it a brand new coil pack that was used as the replacement?

[rane]

Brand new. Ouch, that hurt.

[Fast Ivan]

just to be sure get a multimeter and check the coil resistance

[rane]

just to be sure get a multimeter and check the coil resistance

Right. That's an easy way to make sure the new one isn't a dud. I wish I knew that trick earlier. Learning a lot... the hard way.

[Fast Ivan]

see here on how to check the coil

http://www.theminifo...oil-pack-check/

[rane]

see here on how to check the coil

http://www.theminifo...oil-pack-check/

Thanks. I'm still wondering if it is the coil from what all have said and from the readings I obtained. I know someone earlier said they had to try multiple coils. This will certainly put that to rest. Thanks for putting this together for all of us.

[rane]

Spent quite some time troubleshooting yesterday with a very valuable local resource and forum member. Grateful for his time.

Completed a compression check (normal as expected) and rotated the coil leads around as the mechanic had done previously with no change in the lack of spark or distribution pattern. (No matter which order the leads were attached, 2 and 3 did not get any spark.)

The plugs all looked good but there were several areas of wiring that were taped and appeared somewhat sketchy. I'm wondering if it is a grounding issue? Connections to the ECU were all good.

Things discovered missing or bad:
Bolt to the dog bone to stabilize the engine = gone
Some wiring loose from the thermostat that may make the fan not work as it should
Various other taped areas as mentioned above

But no obvious reason for no spark on 2 and 3

Is expected that even if the leads are reversed that the same middle leads would not produce spark???

Summary:
Compression OK
Leads OK
Plugs OK
Crank Sensor OK
Coil pack - replaced and presumed OK
Scanner revealed Cam and Crank sensor fault in the past - cleared and never returned
Scanner revealed temperature sensor high

Would love feedback. Thanks again to all.

[nev_payne]

That's really surprising especially with an exhaust stroke spark on the MPI system, you'd just expect it to work.

Do you have the MPI circuit diagrams?

[rane]

I do. I have PDFs for the manual, circuits, electrical library, and the handbook for the car itself.