Random missfire/cutoff

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SuluR

SuluR

Buy & Sell Member
Could it possibly be a vacuum/air leak? As changing from a K&N cone filter to standard k11 one made missfire and cut out worse.
 
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SuluR

SuluR

Buy & Sell Member
So I just changed the fuel rail with a spare I had and the problem is still there. However the 4th injected was dirty compared to the rest

4th:
66074BA3-5EAD-4E7C-862C-0E726500DB9D-3951-000006C6261AF047.jpg


Rest are like this:
5CAD92CB-41D5-40AC-ACF1-E4D8D89FD9C1-3951-000006C6330CAC56.jpg


I noticed when I took off the connection to the throttle body idle was almost perfect. But giving it some welly would missfire. And with the connection on, idle is miss firing but driving around seems okay.
 
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SuluR

SuluR

Buy & Sell Member
swapped over with another TB, and car seems much much happier, although now on heavy throttle in gear one it struggles to pick up and the rest of the gears is fine.

What do you guys think of the 4th injector?
 
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SuluR

SuluR

Buy & Sell Member
That was a very useful video Paul. Love Eric the car guy.

I'm pretty sure there's a straight through exhaust on the car which probably isn't helping.

The car is running much better but wants to cut out on load only on low rev. Fuel pump?
 

pollyp

Club Member
yeah i subscribe to ericthecarguy and ETCG1, same guy but different stuff and learn loads.

sure he has a vid bout diag weak fuel pump with a pressure gauge.
woulda thought a weak pump affects mostly during high load high revs where the pump can't keep up?
could the brief on/off throttle judder be looseness in the drivetrain (slack clutch or CV joints) or engine mounts?

mine used to judder suddenly in low gear slow traffic as the injectors switch between "cut-off" (when tps or load is below a cut threshold) and on, was caused by worn soft sloppy mounts. once upgraded to fresh harder mounts there was no more judder and gearstick was alot more precise.
 
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SuluR

SuluR

Buy & Sell Member
yeah i subscribe to ericthecarguy and ETCG1, same guy but different stuff and learn loads.

sure he has a vid bout diag weak fuel pump with a pressure gauge.
woulda thought a weak pump affects mostly during high load high revs where the pump can't keep up?
could the brief on/off throttle judder be looseness in the drivetrain (slack clutch or CV joints) or engine mounts?

mine used to judder suddenly in low gear slow traffic as the injectors switch between "cut-off" (when tps or load is below a cut threshold) and on, was caused by worn soft sloppy mounts. once upgraded to fresh harder mounts there was no more judder and gearstick was alot more precise.

Im not really suffering from a judder, its more like a cut on fuel.

No that you mention it, it finds it very difficult to speed up at high speed, but fine low. I assumed it was the dizzy not timed as low rev torque is awesome.
 
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