2ZZ Comp running problem

[Gaz mr-s]

Partner Caroline has a 2zz comp bought as a runner approx 2 years ago.  There were a few issues needing sorted including the Compressor clutch failing, & the engine mounting requiring modifying. IACV bother. Coilpacks replaced.
But now it runs consistently albeit with the following issue.

It's got a stutter/misfire that starts at around 3800 revs. In 2nd gear with heavy throttle it stutters briefly, & then revs through it up past 5k no problem. In 3rd, it does the same, but the stutter phase takes longer to get through. Once through it again accelerates cleanly. 

I wasn't able to get it on a quick enough road to check 4th gear, but Caroline says that sometimes it will not rev through the stuttering rev-phase in 4th.

[shnazzle]

Could try a coupe of bottles of octane booster, see if that does the trick? Back when we had the turbo we sometimes had this depending on where we got fuel.

[Gaz mr-s]

Could try a coupe of bottles of octane booster, see if that does the trick? Back when we had the turbo we sometimes had this depending on where we got fuel.

The fuel will most often be bought from the same place, but why would it rev 2000 revs beyond the problem area?

[shnazzle]

Could try a coupe of bottles of octane booster, see if that does the trick? Back when we had the turbo we sometimes had this depending on where we got fuel.

The fuel will most often be bought from the same place, but why would it rev 2000 revs beyond the problem area?

Revs are different from load. Does it happen regardless of whether she feathers in the throttle in 2nd/3rd etc or whether she goes for it?

[deviantmr-s]

Could try a coupe of bottles of octane booster, see if that does the trick? Back when we had the turbo we sometimes had this depending on where we got fuel.

The fuel will most often be bought from the same place, but why would it rev 2000 revs beyond the problem area?

Revs are different from load. Does it happen regardless of whether she feathers in the throttle in 2nd/3rd etc or whether she goes for it?

When I go for it. Gently does not cause the issue.

[shnazzle]

Could try a coupe of bottles of octane booster, see if that does the trick? Back when we had the turbo we sometimes had this depending on where we got fuel.

The fuel will most often be bought from the same place, but why would it rev 2000 revs beyond the problem area?

Revs are different from load. Does it happen regardless of whether she feathers in the throttle in 2nd/3rd etc or whether she goes for it?

When I go for it. Gently does not cause the issue.

Thought so. Try some more octane booster, see if it's any better but something has changed. It sounds protection kicking in. It's not liking the o2 readings, knock or misfires it's getting and cutting spark.

What spark plugs? Coil-packs definitely 2zz coil packs? Did it start after they were put in? 
Air filter clean?

[Call the midlife!]

Is the belt keeping tension? Might be slipping on the harsh acceleration and not supplying the air the trims are expecting, then picking up once it's spinning fully again?

[Gaz mr-s]

At least 2 coilpacks were changed..... they are different from 1zz - they don't fit. The running improved.
The correct NGK copper plugs are in

Air filter....it's a paper cone....Pipercross if I remember correctly.  I was going to make up a filter with foam that Petrus mentioned, & the short existing one in front of the battery is LOUD. So I rigged up a temporary longer intake looking for torque, & keeping the maf a good distance from the t/body.
The car didn't run well...."and it doesn't sound as good...."
So the Pipercross was reinstated & set further left to keep the maf further left.

[shnazzle]

Literally could be anything at this point causing either too little or much of something or another. Just needs going down the list of things. Belt slip is a very good shout.

[Gaz mr-s]

Is the belt keeping tension? Might be slipping on the harsh acceleration and not supplying the air the trims are expecting, then picking up once it's spinning fully again?

Don't know, but flooring the throttle & creating torque, it takes off. And in 2nd & 3rd, once through the hesitation, it accelerates hard.

[Alex Knight]

Sounds ignition related.

Also, which ECU?

[Gaz mr-s]

Sounds ignition related.

Also, which ECU?

Corolla

[shnazzle]

Change o2 sensors? Maybe in open loop it's fine but once in closed loop the feedback is false.

[jonbill]

You could try closing the plug gaps. try 0.6mm

[1979scotte]

Let's not overload the op with stuff.

What's easiest and cheapest to start with.
Clean Maf?
Gap plugs?
Make sure it's brimmed with fresh super unleaded?
Correct tension on supercharger belt.

Go from there.

[Gaz mr-s]

Thanks for the helpful posts folks, we can look at those in the next few weeks. (distance apart)  According to what I read when we bought it, the engine doesn't need super-unleaded.  I have heard the occasional knock when I've had the car, but it's only when being careless at very low revs. She has a lead-foot, but when checked, the mpg has been very good.

Octane booster has been ordered.

[AJRFulton]

I think with something like that it's always worth just checking the connectors.

My car had developed a stutter/hesitation that I couldn't diagnose last year - ended up being when I took the cam sensor clip off I had cut a tie wrap. A tiny bit of plastic from the tie wrap had lodged in the connector plug. Whilst it was still connected, it was enough to make the contact not perfect.

It's a 5 minute job to check the plugs for corrosion or what

[Alex Knight]

Sounds obvious, but any pending/stored ECU fault codes?

[shnazzle]

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

[Gaz mr-s]

Sounds obvious, but any pending/stored ECU fault codes?

None

[thetyrant]

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

Agreed if you heard knock it was very bad news, even knock you cant hear without listening device is causig potential damage.

Im guessing the car is run on supermarket normal unleaded ?  if so that could well be the problem as above a highly stressed car like this will benefit from Super unleaded especially if driven hard like you say, sure yes it will run on cheap normal fuel but is it the best thing, absolutely not imo.

The Ecu will adapt to knock from poor fuel to a degree but isnt a guaranteed failsafe, you should not be able to hear knock no matter how you drive it if everything is well.

Octane booster is nasty stuff i wouldnt bother personally but as a stop gap to see if it makes a difference worth a shot, i dont like it as you never know just how much difference its making unless you are very careful with how much fuel you add it to etc, also its usually pretty corrosive stuff and as some will no doubt make it down into the oil its not a good thing, better to just use high quality fuel imo or get car mapped for the cheap stuff if thats what you want to run...of course you will then need and mappable ecu so not so simple or cheap anymore.

Hope you get it sorted

[Gaz mr-s]

When Patrick first mentioned octane booster I thought that super unleaded would be worth trying, but before any conversation occurred between myself & MsSupercharged, she'd already ordered it....  

[1979scotte]

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?

[Carolyn]

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?

The good stuff. 97Ron.

[Dev]

At least 2 coilpacks were changed..... they are different from 1zz - they don't fit. The running improved.
The correct NGK copper plugs are in

Air filter....it's a paper cone....Pipercross if I remember correctly.  I was going to make up a filter with foam that Petrus mentioned, & the short existing one in front of the battery is LOUD. So I rigged up a temporary longer intake looking for torque, & keeping the maf a good distance from the t/body.
The car didn't run well...."and it doesn't sound as good...."
So the Pipercross was reinstated & set further left to keep the maf further left.

It does sound ignition related. What kind of coil packs were replaced, generic or OEM new Denso?

I have at one time added faulty performance aftermarket coils and it created these same issues you are describing and what was remarkable is there was no CEL tripped when it would hiccup. Once I returned and replaced with new Denso coil packs the whole system was back to normal.
 I found out from others experience at the time that having  one defective coil is all it takes to make it run irregular not at idle but when driven at certain loads.