Well it was nice to know that a brand new thermostat failed after 3 weeks in the motor. Needless to say, I overheated on one of the coldest nights of the year.

Car ran fine after putting new fluids in it all the way home, about an hour drive.

Went out of state for a couple of days, now the car is running rough, I think the the opti must have got dirty from losing fluids, and all that jazz.

Is there anyway to clean this thing without taking it off the car? Can electronic cleaner be sprayed behind it with a tube on the can?

Or am I **** out of luck, and have to rip the motor apart?

Thanks for your help.



95 LT1

 

To get to the opti, you have to pull the wp, and the crank balancer off the hub. Be carefull to not get any further fluid on the opti. If you did get fluids on/in the opti, it may dry out without damage, or the opti may be fried.

hth

andy schuck

 

If the SES light is on, get the codes pulled.

 

Yeah, that's another fun filled episode.

I have a post in the diagnostics page about that. I built the circuit to interface to the ALDL stream, worked previously on my xp laptop.

Getting data, but missing some stuff in the code on the win 7 machine, tried running xp on that too with no luck.

Looking for a different laptop to use, since all appears to be working.

If ya take it to pep boys, or autozone, they look at you funny when ya tell them it is OBD1, with the OBD2 connector....

 

Show 'em Shoebox's photo:

http://shbox.com/1/xraycable.jpg

 

Well I finally got the codes pulled, and it was a mass air flow sensor failure. Found a broken wire that I fixed. Car ran fine, no codes set anymore, check engine light off.

Ran fine for 2 days, now it seems I am having a misfire at idle, car running a little rough. No engine codes, no check engine light..

1995 LT1

 

Just a further mention, the rough idle is in closed loop.

Thinking now after reading another thread here, that it may be possible I got a fouled O2 sensor due to it running super rich when the MAF wasn't reporting?

 

Just used free scan, and it appears I am getting values for both O2 sensors, I do notice the right O2 is not fluctuation as much as the left and mostly stays in the .300 - .500 range, where the left 02 sensor goes all over the place from .09 - .900 range..

What would be the normal operation.

 

The O2 sensor voltage should vary over the wider range, of 0xx - 9xx mV.

 

head gasket?

 

I'm hoping not.

Don't have any of the signs of water in the oil / etc... Gonna pull the plugs, and see what I see.

Like I said, ran fine yesterday after fixing the MAF sensor..

 

Just checked the spark from the coil, it appears to be jumping good, however it is brownish, and not a hot blue as it should.

I guess time to look at the coil / ICM....

 

Today in the 30 degree weather, I pulled all the plugs, and verified I have spark going to all the plugs, and visually inspected them for signs of possible head gasket failure.. (moisture / flooded adjacent cylinders / etc) Everything appears to be getting good spark.

What would be the next logical thing to check? At this point I am convinced it is the optispark.

Today after checking all the plugs etc, I took it for a quick ride and it died completely on me as if the optispark was totally disconnected. After a while of cooling down, it finally started however it was a little hard to fire.

Is there a way to test the ICM? Since I am seeing spark, it appears that the coil/ICM are working properly, just getting a bad signal from the Opti.

Any thoughts would be great, as I plan on ripping this out tomorrow..

Thanks in advance..

 

Some of the auto parts store can test the ICM. There's a sticky at the top on how to test the opti.