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SLTTRCK
12th November 2025, 04:41 PM
Hey all!
I’ve got a 92 Tb42e gq that isn’t firing all cylinders (I’m pretty sure)

It’s not so much as a missfire but just not firing full stop. I’ve replaced plugs, leads, dizzy cap and rotor, now I’m starting to get worried it might be a bit of a deeper job._.

Some other random info that’s I’ve found along my headfuck journey:
A spark plug was cracked length wise down the ceramic
Majority plugs were rusted(only at the hex and maybe3-4 threads)
Nasty looking vacuum lines that I’m replacing as I find poor ones
Put a whole new in tank fuel pump in recently

I’m leaning towards a compression issue or an injector is cooked but would love other views on what it could be, can provide photos of whatever

mudnut
12th November 2025, 07:29 PM
It might be a blocked or faulty injector. Start the engine when cold. Use a thermometer or feel the temperature of the exhaust manifold (Before they get real hot). The one that isn't as hot is the culprit. Swap the injector with another and do the same test. (follow the safety protocols of depressurising the fuel rail). If the injectors are ok, do a compression test. That will show if a cylinder is dud.

mudnut
14th November 2025, 09:59 AM
Hey all!
I’ve got a 92 Tb42e gq that isn’t firing all cylinders (I’m pretty sure)

It’s not so much as a missfire but just not firing full stop. I’ve replaced plugs, leads, dizzy cap and rotor, now I’m starting to get worried it might be a bit of a deeper job._.

Some other random info that’s I’ve found along my headfuck journey:
A spark plug was cracked length wise down the ceramic
Majority plugs were rusted(only at the hex and maybe3-4 threads)
Nasty looking vacuum lines that I’m replacing as I find poor ones
Put a whole new in tank fuel pump in recently

I’m leaning towards a compression issue or an injector is cooked but would love other views on what it could be, can provide photos of whatever

Any luck with it ?