2zzge splutters and pops - running rough

[trd_st184]

Hey all,
Ive got a 2zzge in my 2000 model Toyota Celica SX and it has the strangest issue.


In the morning when I go to start, it will start after 2 seconds of so but then almost die completely before the revs pick up again.

If I then try and press the accelerator the car starts chugging like a steam engine, where it sounds like its missing (but almost in a repeatable pattern).

Overall power wise the car doesn't feel like it used to either, it occasionally back fires when decelerating (engine braking) and usually has a miss at idle (haven't heard it idle smooth for a while).

I recently put a new set of plugs in it but this didn't seem to make any difference. My mind is pointing to Air mass meter or ignition coils (the coils look original).

I have a feeling maybe one of the ignition coils could have been worn/has a leak when I bought it, and maybe when degreasing the engine I may have wet it that water had got in.

Any help on the matter would be hugely appreciated. Thanks

[maj]

These models have OBD2 I believe? Diag port under the dash. A cheap ELM327 off ebay should diagnose any sensor issues, otherwise yes it will either be coil/lead related, or AFM/MAP sensor (MAP sensor can be cleaned).

[trd_st184]

These models have OBD2 I believe? Diag port under the dash. A cheap ELM327 off ebay should diagnose any sensor issues, otherwise yes it will either be coil/lead related, or AFM/MAP sensor (MAP sensor can be cleaned).

Thanks for your reply. I believe it is OBD2 connector, but the protocols are supposably quite hard to find (many of the ELM327 style diagnostics don't seem to connect to the car).

I bought new coils and a MAF sensor as I am sure they are as old as the car. They should arrive in the mail in the next few days. Will be sure to report back with my findings

Hopefully I can drive it again in its true form hahaha

Thaanks

[MR22ZZ]

Yep definitely sounds like MAF sensor issues. As a quick diagnostic, you can clean the sensor out with electrical contact cleaner. If the sensor itself has failed completely the car will go into limp mode, you will have dash eheck engine light on and the engine will feel very sluggish and refuse to rev above 3000 rpm.

[trd_st184]

Thanks for your reply. Its wierd though because I don't have any engine lights on. Once its warm I can happily drive it around (although it still feels like its a bit more sluggish than it used to) and it will rev to 8000rpm.

I ended up buying a new maf sensor as i am sure it wasn't long ago since I cleaned the Maf sensor (used electrical contact cleaner) so the issue is very strange.

The other issue is that I don't feel the transition from lift as much anymore, it seems to rev a LITTLE bit quicker after 6000rpm but it seems like a smooth power transition, I am sure the note doesn't change at all (not using a pod, stock air box). I suppose there is a chance that the lift bolts are broken but I wonder why it is still revving to before 8000rpm.

[LittleRedSpirit]

Popping and backfiring can indicate lean running condition.

[trd_st184]

Could the fuel filter possibly cause a lean condition too? Or possibly the maf sensor?

[maj]

MAF sensor will be the primary source that affects lean/rich conditions.

[trd_st184]

MAF sensor will be the primary source that affects lean/rich conditions.

Thank you heaps. A good friend of mine mentioned that the MAF sensor is reading all the time even in WOT. Am I likely to see an overall improvement in performance? I am quite sure it isn't placebo that the cars performance has degraded since owning it. It feels flat and throttle response is lacking too. When I first got the car it was easier to bring up speed, these days I feel i'm pushing the car a lot more to do the same thing.

[knightrous]

Check that the VVT solenoids are working.
My 20V ran like a bag of dicks if the VVT was unplugged.

[DX20VT]

The type of MAF sensors they have on them do give problems, and usually wont bring up a fault code or check engine light either unless 100% dead or unplugged.

[trd_st184]

Thank you very much for your help.

I got the codes checked out and there are quite a few that are playing up:

Seems like both the MAf sensor and Ignition coils are stuffed. (coil on plug)

[trd_st184]

Got around to checking the plugs today, Cylinder 1 is pictured at the top, the bottom plug is cylinder 2 (the other 2 cylinders look like cyl 2)

The error codes above may have been caused by us unplugging coils and maf sensor without resetting the ecu (so the computer just detected they were missing). I reset the ecu and they went away (but haven't been for a drive yet)