Jump to content
SAU Community

Recommended Posts

i was in 3rd gear siting on around 60k's and when i started to accelerate the engine jerked (like a chick trying to learn manual), lost power, makes like a popping sound and now it also turns off and when u try start it, it dies and it eventually starts after 6-8 tries

the anoying thing is it plays up, then drives normal for 5min then plays up again

also if it hepls, it only started doing this last night for about 30sec or so, i have driven about 50km today and it was perfect and tonight it was really bad i was lucky to make it home!

any ideas??

mods are: (stock bov)

power fc

nismo gtr pump

fmic

apexi pod

turbo back exhaust

turbosmart boost tap

thanks guys

My guess would be a fueling issue or spark issue. Was that pump installed recently/properly etc etc? Or has your power FC been fiddled with lately? It might be messing stuff up if it's sending the wrong signals now. Other than that I'd check your sparks/coil packs and all connections to them.

Although I just re-read your post and you mentioned a popping noise? Have you checked all your vacuum piping? Check all your IC piping and hoses and stuff too...

Not sure how much help I've been, but at least it might give you somewhere to start. Good luck mate, make sure you let us know how your hunt goes!

spark plugs are copper and been in there for about 15,000k, i had irridium but the guys who dyno tuned the power fc said the spark was getting blown out so they replaced n gapped with copper and i also dropped in spitfire coil packs

the fuel pump is a tomei for a gtr, not a nismo, sorry!!

i have checked the fuel filter its clean, as is the regulator (no moisture in the vac line)

i didnt drive the car today, but i took it for a 15min drive and it was running perfect

so im gonna pull out the fuel pump n check the power wires and fuel pick up sponge thingo

just on another note, i cleaned my airflow meter and i noticed a lot of thick greasy oily crap in the inlet pipe after afm around the bov entry is that normal or related to my problem?

thanks for all the info so far guys!

spark plugs are copper and been in there for about 15,000k, i had irridium but the guys who dyno tuned the power fc said the spark was getting blown out so they replaced n gapped with copper and i also dropped in spitfire coil packs

the fuel pump is a tomei for a gtr, not a nismo, sorry!!

i have checked the fuel filter its clean, as is the regulator (no moisture in the vac line)

i didnt drive the car today, but i took it for a 15min drive and it was running perfect

so im gonna pull out the fuel pump n check the power wires and fuel pick up sponge thingo

just on another note, i cleaned my airflow meter and i noticed a lot of thick greasy oily crap in the inlet pipe after afm around the bov entry is that normal or related to my problem?

thanks for all the info so far guys!

Get some CRC contact cleaner and give it a good spray to clean it up. Will only improve things. Could be related.

Get some CRC contact cleaner and give it a good spray to clean it up. Will only improve things. Could be related.
yeah give it a clean. even if it doesn't fix it, it won't hurt to give it a clean.

as for your plugs, they are getting on a bit for coppers. so probably wouldn't hurt to throw a new set in as well

ok ill give it a go......i checked the contacts in the afm n harness and it looked like brand new

should keep me busy on my day off on thursday lol

does the oil in the inlet pipe as Fangz described mean there is somethin Up with the Turbo?

it depends. it can mean 3 things really. 1: the oil seal in the front of the turbo is shot (not good, but fixed by replacing the turbo and doesn't damage the engine or turbo). although it is common for there to be a very small amount of oil make it past the seal which is nothing to worry about. 2: the engine has some issues with oil coming through the breather hoses caused by blow by (also not too good). both of these issues will be accompanied by the oil level dropping between changes if it is bad enough. that brings us to number 3: the car has had either of the issues in the past, but is all good now and the oil is just there because the pipes weren't cleaned out after the issue was sorted.

it depends. it can mean 3 things really. 1: the oil seal in the front of the turbo is shot (not good, but fixed by replacing the turbo and doesn't damage the engine or turbo). although it is common for there to be a very small amount of oil make it past the seal which is nothing to worry about. 2: the engine has some issues with oil coming through the breather hoses caused by blow by (also not too good). both of these issues will be accompanied by the oil level dropping between changes if it is bad enough. that brings us to number 3: the car has had either of the issues in the past, but is all good now and the oil is just there because the pipes weren't cleaned out after the issue was sorted.

as far as the past goes, i have had the car 5 1/2 years and its been really reliable and i have cleaned out all the pipes/intercooler/afm a while back. the breather has been blocked off as the hoses go into a catch can

how is blow by caused and fixed?? (if i have it)

i replaced the fuel filter and my prob went away for about a week or so. and all of a sudden it did it again (jerking n stalling) last friday night in peak hour traffic and hasnt done it since!! and i have driven to work everyday

ive noticed it only does this at night, like as if the cooler air makes it play up some how??

the anoying thing is it plays up, then drives normal for 5min then plays up again

I'd definitely say it's the AFM. My R33 S2 GTSt was doing the exact same thing. It was a real pain in the ass to diagnose as it was an intermittent problem that would always seem to behave itself whenever a mechanic was around.

The problem usually struck under acceleration at about 3krpm, just before boost. Sometimes it was fine and would pull to 7krpm without a problem, other times it would unexpectedly "cut-out" at 2 to 3krpm, as if the engine was suddenly completely shut off, which would catch me off guard and result in me being nearly being thrown over the steering wheel.

Take the AFM out, get a razorblade, cut the seal away from the plastic cover on it, open it up and resolder the plug connection. I did this with mine even though the solder on the plug looked fine and wasn't broken. Give it a generous blob of solder on each point, chuck the cover back on, re-yakfat it shut, reset your ECU and give it a go. It completely cured my problem.

It's easy enough to DIY, and there's a handy guide here on SAU with pics on how to do this if you need more info:

http://www.skylinesaustralia.com/forums/Fi...-s-t113284.html

First post by the way, I'll get around to posting in the intro forum shortly :(

I'd definitely say it's the AFM. My R33 S2 GTSt was doing the exact same thing. It was a real pain in the ass to diagnose as it was an intermittent problem that would always seem to behave itself whenever a mechanic was around.

The problem usually struck under acceleration at about 3krpm, just before boost. Sometimes it was fine and would pull to 7krpm without a problem, other times it would unexpectedly "cut-out" at 2 to 3krpm, as if the engine was suddenly completely shut off, which would catch me off guard and result in me being nearly being thrown over the steering wheel.

Take the AFM out, get a razorblade, cut the seal away from the plastic cover on it, open it up and resolder the plug connection. I did this with mine even though the solder on the plug looked fine and wasn't broken. Give it a generous blob of solder on each point, chuck the cover back on, re-yakfat it shut, reset your ECU and give it a go. It completely cured my problem.

It's easy enough to DIY, and there's a handy guide here on SAU with pics on how to do this if you need more info:

http://www.skylinesaustralia.com/forums/Fi...-s-t113284.html

First post by the way, I'll get around to posting in the intro forum shortly :)

last night it happened again and i had the power fc on the sensor check screen

and guess what Bitsushiti your right! the afm voltage was .0 something and flashing. so i also say is definately the afm

mayb time for a z32 afm!!

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I myself AM TOTALLY UNPREPARED TO BELIEVE that the load is higher on the track than on the dyno. If it is not happening on the dyno, I cannot see it happening on the track. The difference you are seeing is because it is hot on the track, and I am pretty sure your tuner is not belting the crap out of it on teh dyno when it starts to get hot. The only way that being hot on the track can lead to real ping, that I can think of, is if you are getting more oil (from mist in the inlet tract, or going up past the oil control rings) reducing the effective octane rating of the fuel and causing ping that way. Yeah, nah. Look at this graph which I will helpfully show you zoomed back in. As an engineer, I look at the difference in viscocity at (in your case, 125°C) and say "they're all the same number". Even though those lines are not completely collapsed down onto each other, the oil grades you are talking about (40, 50 and 60) are teh top three lines (150, 220 and 320) and as far as I am concerned, there is not enough difference between them at that temperature to be meaningful. The viscosity of 60 at 125°C is teh same as 40 at 100°C. You should not operate it under high load at high temperature. That is purely because the only way they can achieve their emissions numbers is with thin-arse oil in it, so they have to tell you to put thin oil in it for the street. They know that no-one can drive the car & engine hard enough on the street to reach the operating regime that demands the actual correct oil that the engine needs on the track. And so they tell you to put that oil in for the track. Find a way to get more air into it, or, more likely, out of it. Or add a water spray for when it's hot. Or something.   As to the leak --- a small leak that cannot cause near catastrophic volume loss in a few seconds cannot cause a low pressure condition in the engine. If the leak is large enough to drop oil pressure, then you will only get one or two shots at it before the sump is drained.
    • So..... it's going to be a heater hose or other coolant hose at the rear of the head/plenum. Or it's going to be one of the welch plugs on the back of the motor, which is a motor out thing to fix.
    • The oil pressure sensor for logging, does it happen to be the one that was slowly breaking out of the oil block? If it is,I would be ignoring your logs. You had a leak at the sensor which would mean it can't read accurately. It's a small hole at the sensor, and you had a small hole just before it, meaning you could have lost significant pressure reading.   As for brakes, if it's just fluid getting old, you won't necessarily end up with air sitting in the line. Bleed a shit tonne of fluid through so you effectively replace it and go again. Oh and, pay close attention to the pressure gauge while on track!
    • I don't know it is due to that. It could just be due to load on track being more than a dyno. But it would be nice to rule it out. We're talking a fraction of a second of pulling ~1 degree of timing. So it's not a lot, but I'd rather it be 0... Thicker oil isn't really a "bandaid" if it's oil that is going to run at 125C, is it? It will be thicker at 100 and thus at 125, where the 40 weight may not be as thick as one may like for that use. I already have a big pump that has been ported. They (They in this instance being the guy that built my heads) port them so they flow more at lower RPM but have a bypass spring that I believe is ~70psi. I have seen 70psi of oil pressure up top in the past, before I knew I had this leak. I have a 25 row oil cooler that takes up all the space in the driver side guard. It is interesting that GM themselves recommend 0-30 oil for their Vette applications. Unless you take it to the track where the official word is to put 20-50w oil in there, then take that back out after your track day is done and return to 0-30.
    • Nice, looks great. Nice work getting the factory parts also. Never know when you'll need them.
×
×
  • Create New...