Running rich, gas in oil!! Help!
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This is on my 89 formula with an OBD2/LS1 pcm swap.
My AFR gauge in my car has been reading rich the last few times I drove it. I never saw anything wrong with the car though.
Tonight I checked my oil and its thinned out and smells of gas.
-Fuel pressure while driving is fine, as per my gauge in my car. like 38-42 as always.
-Injectors all ohm at 12-13 hot
-No leaks from Pressure regulator with car on or off
What next? Check for injector leakdown? Can a bad coolant temp sensor cause this? can bad O2 sensors cause this?
My AFR gauge in my car has been reading rich the last few times I drove it. I never saw anything wrong with the car though.
Tonight I checked my oil and its thinned out and smells of gas.
-Fuel pressure while driving is fine, as per my gauge in my car. like 38-42 as always.
-Injectors all ohm at 12-13 hot
-No leaks from Pressure regulator with car on or off
What next? Check for injector leakdown? Can a bad coolant temp sensor cause this? can bad O2 sensors cause this?
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Sounds like an injector is stuck open. It's washing fuel down past the piston rings and ending up in the oil pan. Not a very good lubricant! Also, this can ruin the piston rings/cylinder wall under that injector. This happened to me.
The only running you should do with this engine is just to find the injector.
The injector might be bad OR the wire to the PCM might be grounded. They get power from the INJ fuses and the ground is controlled by the PCM. Check for codes.
After finding and fixing the problem, an oil & filter change is due and pull that spark plug and spray some oil directly into the cylinder.
The only running you should do with this engine is just to find the injector.
The injector might be bad OR the wire to the PCM might be grounded. They get power from the INJ fuses and the ground is controlled by the PCM. Check for codes.
After finding and fixing the problem, an oil & filter change is due and pull that spark plug and spray some oil directly into the cylinder.
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if I were to pressurized the fuel rail and clamp the feed and return lines shut, theoretically shouldnt the fuel pressure gauge maintain pressure? If not....bad injector?
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running out of time and resources, I brought it to a trusted shop. They said my map sensor wasn't reading properly and needed to be replaced first. Updates to follow monday.
(I always figured a map sensor would make the car run much worse than mine was. We shall see)
(I always figured a map sensor would make the car run much worse than mine was. We shall see)
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How is it running??
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all sensors read fine. plugs look fine. fuel pressure is fine with no leakdown. Mechanic says NO fuel in oil, so I must be losing my mind or something.
I'm figuring possible injector spray pattern problems, or a slight header leak I kind of hear, causing a rich condition
I'm figuring possible injector spray pattern problems, or a slight header leak I kind of hear, causing a rich condition
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OK so everything scans fine. No exhaust leaks to be found while I was under the car. Pulled the cap and rotor to check them
![](https://i60.photobucket.com/albums/h29/Racer001/pic1.jpg)
![](https://i60.photobucket.com/albums/h29/Racer001/pic2.jpg)
Look fine to me. The problem is definitely still there. Development though: When cold if I get on the gas too much it backfires through the intake. Once it warms up, it has this rich/stumble problem. I'm going to ohm the injectors cold tomorrow and see what they read. Its definitely running rich though...you can smell it at idle.
Changed the oil today too adn nope, no gas in the oil. Muhbad.
![](https://i60.photobucket.com/albums/h29/Racer001/pic1.jpg)
![](https://i60.photobucket.com/albums/h29/Racer001/pic2.jpg)
Look fine to me. The problem is definitely still there. Development though: When cold if I get on the gas too much it backfires through the intake. Once it warms up, it has this rich/stumble problem. I'm going to ohm the injectors cold tomorrow and see what they read. Its definitely running rich though...you can smell it at idle.
Changed the oil today too adn nope, no gas in the oil. Muhbad.
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While idling I got these temps measured about 1" away from the header flange at the head
#1 160-175*F
#2 170ish*
#3 220-250*F
#4 230-240*F
#5 270ish*F
#6 270ish*F
#7 230-250*F
#8 230ish*F
#1 160-175*F
#2 170ish*
#3 220-250*F
#4 230-240*F
#5 270ish*F
#6 270ish*F
#7 230-250*F
#8 230ish*F
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when cold, all injectors ohm 12.0-12.3 with the exception of #7 that was 11.8
I swapped plug wires with 1/3 and 2/4 and cylinder 1 and 2 are still reading cold.
#1 150-180*F
#2 130-140*F
#3 200-230*F
#4 230-240*F
#5 230*F
#6 250*F
#7 220*F
#8 230*F
I guess next I swap injectors around.
I swapped plug wires with 1/3 and 2/4 and cylinder 1 and 2 are still reading cold.
#1 150-180*F
#2 130-140*F
#3 200-230*F
#4 230-240*F
#5 230*F
#6 250*F
#7 220*F
#8 230*F
I guess next I swap injectors around.
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ok so I checked a bunch more stuff up until late october. Didnt want to just throw parts at the car. Got sick of it and put it in time out for 6 months. Just replaced the o2 sensors and it seems to be running normal again
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