The engine I got "to rebuild", 3800SC 1997 Riviera, ALL the spark plugs that CAME OUT, were Black wet fuel fouled (170K Miles) showing a code for MAF. COULD a bad MAF cause this on the plugs ? it was obviously either too much fuel or not enough spark, Had good compression. ( also had a code for #5 misfire) what else could it be ? The engine is now completely rebuilt, except sensors and coil pack. not in the car yet. Thanks
IF "not enough Spark" what could be the Cause ? So, Before trying to fire up the new engine, Is the Any Way to" TEST" the coil packs (3) and ICM, and MAF to tell if they need replacing ? Can it be done with a multi meter, Or can Advanced or auto zone test them ? Thanks
It is either rich mixture, bad rings or bad valve stem seals. The coil pack will usually work or not work. They can cause misfires, but never cause all the plugs to be oil/fuel fouled. Larry
"WHAT" would cause ALL the cylinders to run Rich ? (I wouldn't think ALL the injectors would leak at the same time) It's not oil, it's gas (That I do know) MAF ? 02 ? Fuel Pressure Regulator ? When I got the car, it always started right up, would run smooth (when Not under load), But had "almost No Power" trying to drive it. had 170 psi in all cyl Before the rebuild. I Probably "Should Have " solved the problem BEFORE pulling the engine, but .... that was then this is now. Is there a way to TEST the "suspect" components out of the car ?
If it has been running that rich for that long then the cat is hosed along with the O2 Sensor. You have spent a lot of money on the rebuild, just replace the sensors related to mixture and be done with it. It is most likely not anything to do with spark. Larry
That's What I want to do, which ones ? 02, already did coolant temp, does the intake air temp do anything, MAF, IAC ? just tell me, Which Ones . Thanks
I was just looking at the Exhaust system that Came OFF of This Engine (from the 97 Riviera). I noticed that one of the 'Wires" on the 2nd Oxygen sensor (After the Catalitic Converter) was burned off. Could THAT have caused the "No Power" situation and the fouled plugs ??
I was just looking at the Exhaust system that Came OFF of This Engine (from the 97 Riviera). I noticed that one of the 'Wires" on the 2nd Oxygen sensor (After the Catalitic Converter) was burned off. Could THAT have caused the "No Power" situation and the fouled plugs ??
We don't use the after cat O2 in the fiero.
------------------ 86 SE Convertible 3800sc 4t65e HD.
I KNOW that. Could that have been causing the problem "when it was IN The Riviera" ? The Riviera "Did use it" for "Something". I haven't gotten it into the Fiero yet, I just don't want to run into the Same Problem AGAIN.
I KNOW that. Could that have been causing the problem "when it was IN The Riviera" ? The Riviera "Did use it" for "Something". I haven't gotten it into the Fiero yet, I just don't want to run into the Same Problem AGAIN.
I don't think so, but you would think its possible if the computers looking for a certain perimeter from the second o2 and is giving the wrong fueling/spark. But I think it would only cause a check engine light.
------------------ 86 SE Convertible 3800sc 4t65e HD.
ok, that eliminates that ! It "DID" "Act" like it had a Plugged Converter or muffler, but it threw the MAF code and misfire on #5. Now it has ALL new internals( with the exception of Rods and Pistons) crank/balancer, rebuilt Super charger, temp sender, plugs, wires, rebuilt TB, water pump, Belts and tensioners, so, I guess about the only "suspects" left are MAF, TPS, 02 sensor, MAP.
