Spark Plug Badly Fouling on Cylinder 1 - 2ZZGE Motor - Also bad idling

[trd_st184]

Hey all,
I've been having trouble with my ride for the last few months and can't seem to fix it. 2001 Toyota Celica zzt231 with 2zzge motor.

Symptoms
- Cylinder 1 spark plug is always fouled (tried swapping spark plugs with other cylinders and Cyl 1 will foul the plug every time).
- After around 8-10 seconds on cold start the car will begin to hesitate to the point of nearly stalling. If you rev it seems like it suffocates more (but get it at the right amount of gradual throttle and it picks up fine).
- Car has a constant hesitation when cruising, you can feel it through the car (although minor).
- Car has felt like its lost a lot of response. Seems like a struggle to bring up to speed compared to what it used to be.

I tried replacing Ignition coils and new spark plugs but still the same issue. The problem goes away when I swap plugs around (cyl one plug goes to cyl 2 and cleans off, cyl 2 goes to 1 and fouls up).

I thought it might have been MAF sensor but it wouldn't just foul one plug. Maybe could be leaking injector?

Any thoughts to solve this really annoying problem once and for all? Would be hugely appreciated.


See pic of fouled plug below:

[trdee]

if coils dont fix it then it could be injector related, or coilpack wiring related. pull the injectors out and go get them tested and find out

[davew7]

"pull the injectors out and go get them tested and find out[/QUOTE]

Way to much fuel in cylinder one. Just replace the injector in cylinder number one. [less down time then waiting for injectors to be clean and returned from the shop] Also lube the injector seals before replacing, much easier to replace and less chance of tearing the rubber seals.
Dave W

[trd_st184]

if coils dont fix it then it could be injector related, or coilpack wiring related. pull the injectors out and go get them tested and find out

Thanks for the info will definitely have a look at injectors.

pull the injectors out and go get them tested and find out

Way to much fuel in cylinder one. Just replace the injector in cylinder number one. [less down time then waiting for injectors to be clean and returned from the shop] Also lube the injector seals before replacing, much easier to replace and less chance of tearing the rubber seals.
Dave W

Thanks heaps will definitely check this out. If the plug is that bad at the moment is it likely its not just a placebo effect that the car is down on power and response?

[Joel_mcd]

A fouled plug like that can cause misfiring, difficult starting and hesitation when driving.

It's worth checking your oil too as the overfueling could be washing down the bore of cylinder 1 and mixing with your oil. If the oil smells of fuel at all, remember to change it once you've fixed the issue.

[Shakotan_Aaron]

Id surgest doing a compression test. If the compression is low it may not have enough to fire or not until it warms up.

Injectors can definately leak, if they are not too hard to remove, id surgest swapping the suspect injector to another cylinder. There is labour time, but not parts cost.

[trd_st184]

Thanks for all the suggestions. The strange thing is it actually fires up fine when you first go to start it but its only after about 10 seconds or so does the issue actually start. Sometimes it happens when the car is fully warm and the car has been driven around for a while (nearly stalls at the lights).

[trd_st184]

Hey all,
I must admit I have still not fixed the issue. I have only come back to looking at it now (a few months later)

I was going to have the injectors serviced but I am a bit hesitant on throwing money on the car if it might not end up fixing the issue.

[allencr]

...hesitant on throwing money on the car if it might not end up fixing the issue.

Then just swap'em.
What's the compression????

[StuC]

move the injector to another cylinder and see if it fouls that one.

[Blackcountryboy]

sorry to hijack your thread, I'm having a simiarish issue. Fresh rebuild, head and bottom end. Plugs 1 and 4 are sooty. Plugs 2 and 3 look shiny black oily. Have bettween 190 and 175 compression across all cylinders (3sgte).

You name it I've checked it. Struggles to start then dies after a min or two as it starts to gets warm. Shakes and knocks like a b@stard. Cel light on but no codes...

Been trying now for 2 months to get her to run and idle.

Any thoughts at all anyone?

Hope you've had more luck than me btw with plug one dude.

Thanks!!!

[jondee86]

Fresh rebuild, head and bottom end. Plugs 1 and 4 are sooty.
Plugs 2 and 3 look shiny black oily.

Sounds like all cylinders are running mega rich. If your engine uses a MAP sensor, make sure the vacuum hose hasn't fallen off.

Cheers... jondee86

[jondee86]

The strange thing is it actually fires up fine when you first go to start it but its only after about 10 seconds or so does the issue actually start.

Sounds like the injector is stuck open. When the engine is cold and needs extra fuel, that might not kill the plug, but as it warms up the mixture in that cylinder will go past the rich misfire limit (around 8:1 AFR). Try disabling that injector (remove the clip) and see if the engine runs consistently on three cylinders. Otherwise do as suggested and swap the injector to another cylinder, or obtain (borrow/buy/steal) one injector to replace the bad one.

Cheers...jondee86

[trd_st184]

Hey all,
I finally got around to doing something about it. Ends up cylinder one injector was putting out more fuel than the others.

Got em cleaned the one problematic fuel injector actually ended up putting out even more fuel.

The final measurements were 70-64-64-64. The guy that did the work (highly recommended) mentioned that the mechanism is probably quite worn and not closing up soon enough.

I ended up getting another set cleaned and the car runs beautifully now. So much more response and goodbye to constant backfiring haha

Thanks again to everyone for helping. Wish there was a like/thanks button to everyone