1986 Toyota 4Runner is running rich.

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Apr 22, 2018 | 03:11 PM

Gerard990

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From: North Carolina

1986 Toyota 4Runner is running rich.

Recently bought an 86 4runner. I’ve been fixing up little things that have been wrong with it and I recently started to try to diagnose the fuel smell I was getting while running down the road. Found out my timing was off by 10 degrees and was able to fix that. While my gas mileage has improved slightly I’m still getting a ridiculous amount of gas smell coming into my cab. I’ve already tried looking at the fuel lines for leaks and can find none. My egr is closing properly. I just bought a new charcoal canister, not 100% sure that will help but I figured it can’t hurt anyways. I’ve done some research on adjusting the tps screw but I’ve heard mixed results about it working and it making it worse. Any help on finding why it’s running rich and burning so much fuel would be a great help.

Apr 22, 2018 | 03:26 PM

millball

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From: Southern Arizona

'Burning so much fuel' might be another mans 'great mileage'. Got any empirical data on what mileage you are actually getting?? Any stored codes??

There should not be substantial unburned fuel smell in any case. Investigate that further.

Proper tune-up using high quality parts, maybe new Denso, or NTK O2 sensor. Determination of proper TPS function and adjustment. Then determination of true base timing.

Determination of ECU temp sensor function and determination of whether ECU goes into closed loop operation.

Lottsa things to be looked at.

Apr 22, 2018 | 04:51 PM

Co_94_PU

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From: Colorado

Is the exhaust intact, is the rear window closed, no big gasping holes in the rear fenders.. Does changing the fresh air selector male a difference in the cabin odor..

You've got a fuel leak, be it badly plumbed lines or full on leaks that vehicle should not be driven. You are risking yours, fellow drivers and first responder's lives..

Fuel tends to evaporate quickly, your best bet for finding a leak is with the engine cold by jumping the fuel pump diagnostic port and of course your eyes and nose..

Likely culprit is the pulse damper. Located at the end if the fuel rail.

May 11, 2018 | 08:33 AM

Tims86Toy

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Have you checked your Cat converter? I realize your 86' is a TPS but my carb'd version came with the same issue when I first bought mine. I wound up removing the CAT and blocking off the EGR (it failed). If it's been running too rich for too long then the CAT will probably be plugged so you'll never get it to run right. And installing a new CAT on a badly tuned engine will lead to the same problem.