2ZZ Comp running problem

[shnazzle]

I mean, it sounds exactly like what we had with the turbo we had. The only thing that solved it was changing ECU. Or, of course, we could have had the piggyback remapped. As you're using an OEM ecu, it's clearly not the "tune" that's off, but the parameters it is working with.
Summarising above;

- try super unleaded/octane booster (agreed with thetyrant, use octane booster to quickly diagnose, not as a solution. I only said octane booster so that you didn't have to empty your tank and fill it up again )
- Some basic OBD2 checks
   - Misfires
   - fueling (spiking lean/rich on load?)
   - o2 sensor voltages look as expected? Nothing flatlining? Don't know if you still have EML light enabled after swap.
   - vacuum (sign of leaks?)
- check that spark plugs are correct for the Corolla 2zz SC. Guessing same gap but colder. 
- wiggle all the coil-pack wiring and re-plug. check that coil-packs are in securely.
- clean MAF, ensure no leaks
- check belt. Make sure it's tight (not too tight) and clean.

[deviantmr-s]

I mean, it sounds exactly like what we had with the turbo we had. The only thing that solved it was changing ECU. Or, of course, we could have had the piggyback remapped. As you're using an OEM ecu, it's clearly not the "tune" that's off, but the parameters it is working with.
Summarising above;

- try super unleaded/octane booster (agreed with thetyrant, use octane booster to quickly diagnose, not as a solution. I only said octane booster so that you didn't have to empty your tank and fill it up again )
- Some basic OBD2 checks
  - Misfires
  - fueling (spiking lean/rich on load?)
  - o2 sensor voltages look as expected? Nothing flatlining? Don't know if you still have EML light enabled after swap.
  - vacuum (sign of leaks?)
- check that spark plugs are correct for the Corolla 2zz SC. Guessing same gap but colder.
- wiggle all the coil-pack wiring and re-plug. check that coil-packs are in securely.
- clean MAF, ensure no leaks
- check belt. Make sure it's tight (not too tight) and clean.

Thank you for your responses, very helpful. I am using the octane booster to diagnose as have three quarters of a tank left. I have a list to work through now, so thank you everyone for taking the time to help.

I will let you know how I/we get on.
 

[Alex Knight]

Reset the ECU after filling the tank.

[Gaz mr-s]

The question was asked previously if the eml works....it doesn't. So it's regularly OBD checked.  Coilpacks have been mentioned as a possible problem-source.

When the car was bought & work was done to sort out some issues it had misfire codes. So two coilpacks were  replaced...new aftermarket. 

If coilpacks are again an issue, why are there no codes?

[potge]

The question was asked previously if the eml works....it doesn't. So it's regularly OBD checked.  Coilpacks have been mentioned as a possible problem-source.

When the car was bought & work was done to sort out some issues it had misfire codes. So two coilpacks were  replaced...new aftermarket. 

If coilpacks are again an issue, why are there no codes?

There is a chance the misfire is just below the OBD threshold (which I have no idea if it will be consecutive counter or a counter over a period of time or a mix of both).

Is there any chance you can try with 4 identical coil packs? and reset the ECU before that.

[Gaz mr-s]

/quote]

We're looking at getting some.

[Ardent]

I would argue there should never be any knock, no matter what load. And I would also argue that super-unleaded is the only way to go on a high-compression engine with an added supercharger. Partially because the super-unleaded meets higher standard and there's much more variability in the normal unleaded. especially if the unleaded is E10. You could literally have up to 10% ethanol in there which, on a high-strung car like that, to me is a bit of an no-no unless it was mapped for flex-fuel

I agree 100% with this.
The 2zz is a high compression engine you're now adding boost which ups the effective compression ratio even higher. It surely needs a minimum of 97 Ron fuel.

@Ardent what does toyota specify for the tte turbo?

@Carolyn what fuel do you use on the supercharged 1zz?

98

[Dev]

The question was asked previously if the eml works....it doesn't. So it's regularly OBD checked.  Coilpacks have been mentioned as a possible problem-source.

When the car was bought & work was done to sort out some issues it had misfire codes. So two coilpacks were  replaced...new aftermarket. 

If coilpacks are again an issue, why are there no codes?

There is a chance the misfire is just below the OBD threshold (which I have no idea if it will be consecutive counter or a counter over a period of time or a mix of both).

Is there any chance you can try with 4 identical coil packs? and reset the ECU before that.

It is believed that might be the case and the faulty coil not giving the ECU the signal the coil misfired. 
This is a known issue with generic aftermarket coils. Sometimes they work initially and get worse in a short period of time, and if you have one bad one it creates glitches in the form of hesitation from the entire ignition system.
The factory Denso coils are expensive but worth it. 

[deviantmr-s]

Coil packs were changed and it runs considerably better. The drive down to Wrexham and back put the smile back on my face. Running completely now on 99 ron, where as before I ran a mixture of standard and premium.

I will however be keeping a close eye on it.

Thank you for all your help. 

[1979scotte]

Coil packs were changed and it runs considerably better. The drive down to Wrexham and back put the smile back on my face. Running completely now on 99 ron, where as before I ran a mixture of standard and premium.

I will however be keeping a close eye on it.

Thank you for all your help. 

Keep putting 99 in it and you'll be fine.

[thetyrant]

Hopefully it's all sorted

[Gaz mr-s]

It is believed that might be the case and the faulty coil not giving the ECU the signal the coil misfired. 
This is a known issue with generic aftermarket coils. Sometimes they work initially and get worse in a short period of time, and if you have one bad one it creates glitches in the form of hesitation from the entire ignition system.
The factory Denso coils are expensive but worth it. 

This seems to have been the case. When the car was bought I think all 4 were Denso, but it had misfires, & they did produce OBD codes.  Nothing helpful like this with the Aftermarket in.  When we got 3 replacement Denso, (1 new, 2 used) we discovered that of the current ones, 3 were aftermarket.

Caroline says there is still a slight hesitation in 4th gear only, so we're going to get a couple more new ones from the US because without any kind of offer they cost over £60 each here....  

[Dev]

It is believed that might be the case and the faulty coil not giving the ECU the signal the coil misfired. 
This is a known issue with generic aftermarket coils. Sometimes they work initially and get worse in a short period of time, and if you have one bad one it creates glitches in the form of hesitation from the entire ignition system.
The factory Denso coils are expensive but worth it. 

This seems to have been the case. When the car was bought I think all 4 were Denso, but it had misfires, & they did produce OBD codes.  Nothing helpful like this with the Aftermarket in.  When we got 3 replacement Denso, (1 new, 2 used) we discovered that 3 were aftermarket.

Caroline says there is still a slight hesitation in 4th gear only, so we're going to get a couple more new ones from the US because without any kind of offer they cost over £60 each here....  

 The aftermarket ignition coils come in all types from very cheap to rebranded Denso coils. Its hard to know what you are getting but a good indicator is the price and the feel of the plastic being thin.  What I believe happens is the quality of the windings is not there and over time with heat the coatings wear and it starts to short progressively leading to misfires but since the aftermarket coil cuts corners it doesn't always send a signal to the ECU that it has misfired. 

 The OEM Denso coils also shorts over a period of time gaining in resistance. I have tested this on a multi meter comparing old coils and new ones but there was no way to use that as a guide to know if the coil is tired.
 I then did some searching and found that these ignition coils go bad like most things electronic even if they sit brand new for a very long time due to deterioration and atmospheric corrosion. This also happens with ECUs and just about anything electronic. Time is your enemy. 

 In a nut shell I would not use used ignition coils. I have found that although I did not have any faults with my old  ignition coils they were tired being 13 years old and once I put a fresh pair in the car felt like it gained 10hp and was lively. Therefore I believe it is a good investment to refresh the ignition coils with new stock every 10 years with a new set of plugs for peak performance.