foot to the floor and no increase of rpm

hi guys z is having a issue 89 tt auto .

what i have tripple checked so far:

replaced s2ptu
all new injector connectors
pulled coil packs at idle (i noticed change)
inspected spark plugs all seem fine apart from one which had a little oil on the white side of the spark ( they are less than 8 mnths old platniums from gb a while back) i also have a slight rattle under acceleration under the plennum .
all vacume lines seem to be in place from what i can see but how many are there
tripple checked all wiring and i am 100 % certain its all correct

Problem which occurs off and on whilst driving - idles fine but it runs rough between 2000rpm and 2500rpm whilst in park and whilst driving,

after 10 mins driving when it warms up it starts running really sluggish (foot to the floor) and it wont pick up speed at all !! untill turbo kicks in and speed increases but not to full potential

I am getting a warning light come on occasionally, when this happens it gets a lot worse (rectangle box with steam coming off it) it will dissapear after a short while, the car sometimes returns to normal other times it still runs like crap for a short period after light goes out but comes good eventually .

i havn't completed a compression test, i don't know how, i can do some basic things here and there .
any help is appreciated
would a datascan point me right to the problem if so can anyone around bris or gold coast help with this

 

that warning light is a cat warning light check to see if your cats are blocked

 

is that just un bolt and look through ? never had to do it before

 

Cat warning light will come on from unburnt fuel. Sounds like you have an injector issue. Tapping noise under plenum is most likely hydraulic lifters, but could also be something alot more severe given the other symptoms. Rough running, sluggish and cat overheat are symptoms of a melted piston, but this will not be intermittent as your issue seam to be.

Consult scan should be your first check point. Use consults cylinder performance test and check out the results for where to look next.

 

after i put the spark plugs back in, which was the last things i checked on the z i took it for a very short drive and it had heaps !! of power i had plenty of wheel spin just from taking off i thought prob was fixed assumed dirty spark or coil pak cable not sitting right but on the way to work this morning problem occurs again, i had loads of power would that mean a melted piston is out of the question ? I did over heat 6 months back but as soon as i noticed temp gauge increasing it got shut off but is was on the high end of the gauge

 

how old are the plugs and are they the correct ones. I would suggest getting a set of copper replacements as they are a cheap way of checking if you have bad plugs and they can handle being cleaned (IMO never try and file iridium or platinum plugs) if they have fouled. I also believe they are more tolerant of your engine being on the wrong side of good and take more to foul

 

By the sound of that the plugs are fouling, points back to an injector issue. Do the consult check to isolate to a cylinder then begin the checks on that injector.

 

i had similar symptoms a while back, itd run like a dog for a while, no guts at all, cat warning light would come on then five minutes later itd run normal again.
mine tended to play up after a bit of leadfooting.
turned out i had a faulty injector.

 

anyone in bris or gold coast able to do consult check please !!!!

 

Pm sent.

 

I had the same problem a few years back. Ended up being low compression in 1 cylinder.

 

Hello , did you not see a2zed's ad at the bottom of his reply
Would be a great spot to start

 

Cyl 3 only dropped around 20rpm from memory. Detonation sensor needs bypassing with a resistor. The rest was ok.

 

i have just replaced spark plug and injector connector wires and still no change, off to jay car now to get a resistor but would the detination sensor cause #3 to drop rpm ?

 

No but it does put you in safety boost which is only 6psi, you'll get 9psi automatically with it fixed. The injector itself might be stuffed on cyl 3

 

Correct me if I'm wrong(I know that bit of advice is unnecessary)but when an engine drops rpm(runs rough)after removing the ignition to any cylinder, that indicates that it was working OK beforehand, nes par?

BTW, it is impossible for a single cylinder to drop rpm, unless ALL cylinders do the same.:zlove:

 

Compression test that cylinder.

 

By stopping cyl 3 total rpm only dropped 20rpm. worded better?

 

which program has that? is it free?

 

I dunno about all of them but I have Conzult Tuner and Nissan Datascan, out of those two only Conzult from memory has the power balance test. It's not supposed... to be free but you know. maybe.