That's some gremlin you've got there, Ghost.

Could the fuel system be at play here? Issues with either the fuel pump or the strainer?

 

I also thought that at first, so I have a new fuel strainer sitting here just waiting to get swapped in. Just another item to try, I am trying to be as descriptive as I can for guys that develop the same issue as well I want to just change one item at a time so the issue can be better pin pointed.

 

Can we get a list confirmed of what operates at wot? Sounds just like my car does. deff interested in this as I will be throwing parts at mine shortly. Plan on keeping the car for a while so I dont mind spending money on parts I know will go to good use.

 

Okay I cleaned the MAF sensor today with CRC sensor cleaner to see if the same issue's were present as well without jumping to wot, I started off in 2nd (drive 2) and let the cars rpm's go up naturally to just into the 4000 rpm range no bogging/misfire, slipped into 3rd (drive 3) and again just let the car build in rpm naturally to 4500 rpm and again no bogging/misfire. I then tested the car in 2nd (drive 2)on a roll at about 20kmph and then jumped to wot and the car bogged/misfire at just over 4100rpm, then attempt the same test in 3rd (drive 3) from a rolling run at 20 kmph and then jump to wot and same thing right at 4200 rpm the car bogged/misfire. So the different drive gears present the same issue under wot conditions. Rochester suggestion of the fuel delivery system could have some relevance as the demand for fuel under wot seems to intensify around the 4200 rpm range, of course I guess that could be said about several systems on the engine when you hit that range.

So to-days testing only showed me that the same issue presents its self in any of the drive gears and at roughly the very same rpm range.

 

The fuel strainer is an inexpensive maintenance item, and should give you peace of mind at the very least, even if it has no effect on your problems. Of course, if fuel delivery is the issue, and it's not blockage in the strainer, that means your pump itself, right? And if you go that route, at least you'll be familiar with things having replaced the strainer.

The pump and strainer are supposed to be lifetime items. Hmm... good luck, Jim.

 

Still need that 7/8 throttle test. (still putting the engine under high load but not at WOT). Need that test in the 'manual shift' and 'auto', automatic will obviously not rev as high.

I still suspect TPS as of this point. Awaiting results of the test above.

I don't think firing up the parts cannon is necessary yet, we have more diagnostics.

Sorry I had a hectic day I was going to try and start a list of functioning sensors during WOT. If someone could start it that would be great, I've got another busy day tomorrow and a teething son to take care of, I'll do my best, but I need that test Ghost.

 

I know resurrecting a dead thread is bad, however I have this exact issue and there was not a resolution. I swapped an 05 VQ35 into my 02 max. I used the lower oilpan, cam sensors, and crank position sensor from the old engine. Injectors are from the old engine as well. The front cat is gutted and the rear is in good shape.

O2 sensors are fluctuating somewhat equally on both banks.

I do get a P1800 but it may be because I exercised all the connectors to make sure they were plugged in.

Mine does fine until I hit 4200 and then sputters and pats until about 6200 and then pulls hard all the way into the rev limiter.

To me that says something brain wise is going on.

Ideas?

 

I'm having exact same issues, wish someone found a solution

new MAF, new cam sensors, bad precats but I'm going to deal with them as soon as I find good deal on headers...

It's always at 4000-5000 and it's a dramatic misfire, but if I give it slow throttle it manages through it...

 

Im having this same exact issue..did anyone ever find a solution?