Gas in oil

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jeff540
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Gas in oil

Postby jeff540 » Fri Jul 26, 2019 3:17 am

Was checking my oil,and found the dipstick overfilled with oil and gas,car has been sitting,runs great,plan on oil & filter change tomorrow,i do not drive this car much at all,getting mixed reviews,stuck injector or injectors,bad pressure regulator,even read could be TPS.anyone ever deal with this,95 Z26 3100 auto. Tia.



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Rettax3
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Re: Gas in oil

Postby Rettax3 » Fri Jul 26, 2019 12:43 pm

Had that problem once on my '89 RS Camaro (5.7 Police Special engine swap from a same-year Caprice detective-car). It was a leaky injector, the car was in my garage with the back-end lifted up while I worked on the BW 9-Bolt rear axle, which took a while as parts have very limited availability outside of Australia for that rear-end. The injector managed to dump quarts of gas into the engine. Definitely do NOT start/run that thing with gas in the oil- it thins it down killing viscosity, and washes the oil-film off the bearings. The next start-up would be the hardest start ever on that engine. Let alone the added fire risk. :no: If the car is running well, the issue almost certainly won't be the fuel pressure regulator. If it is leaking badly enough to pump fuel into the engine in that kind of volume, the engine won't run right. A leaking injector is far more common, and if the car sits a long time a leaking injector doesn't have to be severe enough to cause a runability issue.


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

jeff540
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Re: Gas in oil

Postby jeff540 » Fri Jul 26, 2019 2:33 pm

Thanks for reply,will do oil change.any help finding which fuel injector is stuck open



jeff540
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Re: Gas in oil

Postby jeff540 » Sat Jul 27, 2019 12:44 am

Was not gas,was coolant,changed out original 3100 because of the junk gaskets.started to knock,swapped it in 2010 with a 3100 out of a wrecked 96 corsica,with 131,000.guy sold me engine and tranny for 250.00.been fine til now.changed oil and filter tonight,got out 6 quarts oil and coolant.pulled off top rad hose,poured in bottle of stop leak.filled with coolant,bled system,took car around town even went out of town,put 70 miles on it.temp ran a tad above normal at all times,came back checked the oil,looks good,top rad hose had pressure.soon i might have to do the LIM gaskets with felpro.or sell the car,i have a 03 impala with a 3400,runs great,but dont drive it because of crazy new york rust....if and i mean if...i decide to go 3400 do i need the tranny from the impala?



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Rettax3
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Re: Gas in oil

Postby Rettax3 » Sat Jul 27, 2019 1:48 am

No, you don't need to swap the tranny, or much of anything else. 3400 pretty much drops in place of the 3100. EGR is different for sure, but your Beretta's PCM will run the 3400 just fine. I do believe the 3400s may have received a different impedance type injector somewhere around that time though, so watch out for that -if the injectors are long and skinny, either keep your 3100 units or get an older set of 3400 injectors, also the same on the older 3800 Series 2 N/A engines... There are a few swap threads around here that will have all the details for you... Pretty common and easy swap. I really hate those plastic LIMGs, thanks Chevy...


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

jeff540
Registered User
Posts: 133
Joined: Tue Jun 08, 2010 2:39 am

Re: Gas in oil

Postby jeff540 » Sun Jul 28, 2019 8:30 am

Checked oil again,and is fine.don't know what's up,will keep an eye on it.



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Rettax3
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Re: Gas in oil

Postby Rettax3 » Mon Jul 29, 2019 5:40 pm

As it is a 3x00, it is a fairly safe bet you have a LIMG failure. When they start to go, sometimes it only passes coolant out intermittently -remember, the problem is GM's crappy plastic gaskets crack and fall apart, but they still have a silicone bead in them that actually seals the coolant passages, the plastic itself is only there to hold the silicone where it is supposed to be. Pressure changes inside the cooling system can push the silicone around, causing leaks sporadically at first.

There are other places the engine could develop internal leaks, like the timing case for instance. If the car has sat for a long time, simple condensation can cause a buildup of water inside the engine, but it seems unlikely it would have enough to be confused for a coolant (or fuel) leak into the engine, especially since you've already experienced it before.

I would suggest either fixing the leak properly or at least check your oil regularly -before every cold start-up wouldn't be too often. The problem could well have 'fixed' itself for a substantial time, if the silicone bead inside the LIMG rolled or pushed itself into a new position where it has some backing from the broken plastic carrier... And you did say that you dumped in some sealant -sometimes that helps a little, though I personally wouldn't trust it.


1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26

jeff540
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Posts: 133
Joined: Tue Jun 08, 2010 2:39 am

Re: Gas in oil

Postby jeff540 » Mon Jul 29, 2019 7:56 pm

Thanks Rettax3




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