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ive changed my intercooler piping, and yes ive made sure its all tight with no leaks etc, the car boosts fine, but when its warm it tends to slowly die, as if there is a fuel issue, but i didnt touch anything with the fuel system, the car jerks a little and continues so for a little bit then just stalls while moving. it can run fine and feels normal, but after a bit of driving it will start to do this, as if the ecu is cracking the shits and stops fuel or something.

the only thing different to the last intercooler piping setup is that the actuator hose that used to come from the cooler piping just before the throttle piping and goes to the manual boost controller, is now Teed into the hose that goes from the TB to the stock BOV because the new piping dosent have anywhere for the hose to connect to.

its an r33 GTST S1. any ideas? do i need to drill a hole into the new piping?

PS. also, i dont know if this would have any affect but i took the valley cover off and left the unit thingo at the back that usualy bolts to the valley cover just dangling next to the firewall.

Sounds like mass air flow meter, changing piping could be unrelated or you gave it a knock in the process (check the plug on the back).

Try bolting that ingnition moduel back to some thing and make sure it earthed.(best place is firewall)

Edited by AZZA R34
Sounds like mass air flow meter, changing piping could be unrelated or you gave it a knock in the process (check the plug on the back).

Try bolting that ingnition moduel back to some thing and make sure it earthed.(best place is firewall)

where is the maf? is that the same thing as the afm?

does that ignition unit at the back of the center vally cover need to be earthed? it was only bolted to it, no earthing wires anywhere...

edit: i found out the afm is the same as the maf...

i forgot to mention, at the same time i changed the spark plugs, i thought it was odd that the previous owner had put in 3 iridium and 3 normal spark plugs, i replaced them all with new standard plugs, heat range 6 gapped at .8mm

Mass Air Flow (MAF) = Air Flow Meter (AFM) there pretty much two names for the same thing

check the plug on that etc.

Id probably also put your valley cover back on and put the ignitor (that unit at the back) back onto it, its not something you want to leave hanging, its got alot to do with your spark and should be mounted as far as I'm concerned

find another sau vic member in your area and offer free beer/pizza to come over and help

you have posted quite a few threads lately which would be easier to diag/check/test with someone local

you could also compare their car to yours to see and try and isolate the source easier

just a thought

Mass Air Flow (MAF) = Air Flow Meter (AFM) there pretty much two names for the same thing

check the plug on that etc.

Id probably also put your valley cover back on and put the ignitor (that unit at the back) back onto it, its not something you want to leave hanging, its got alot to do with your spark and should be mounted as far as I'm concerned

ahh ok, well i checked it and the plugs fine, not sure about the afm itself though, if it was buggered wouldnt the car run alot worse?

find another sau vic member in your area and offer free beer/pizza to come over and help

you have posted quite a few threads lately which would be easier to diag/check/test with someone local

you could also compare their car to yours to see and try and isolate the source easier

just a thought

i dont know anyone on here sorry, so the best i can do is try get as much help as possible from people with knowledge

if your AFM is stuffed it will usually run pretty crappy

but if the connections in the plug are a little dodgy it might run fine for a bit then stuff up. easy way to check your cooler pipes are all good is to get some aerostart or something in a spray can that is flamable and spray it around intercooler pipes, if engine revs up then u have a leak in your cooler pipes. This is usually done at idle

if your AFM is stuffed it will usually run pretty crappy

but if the connections in the plug are a little dodgy it might run fine for a bit then stuff up. easy way to check your cooler pipes are all good is to get some aerostart or something in a spray can that is flamable and spray it around intercooler pipes, if engine revs up then u have a leak in your cooler pipes. This is usually done at idle

ok will look into the spray

but

you got me thinking about the wireing to the afm...

the wireing to the plug which connects to the afm is dodgy (last owner), the wires are all soldered properly together, and while i was fitting the piping i was in a fixit mood and decided to wrap the individual wires with insulation tape so they dont touch eachother or watever, who would of known it mightve made it worse... so i guess ill have to look into fixing them up properly (even though they are properly soldered etc)

update, after some extensive research a lot of people are suggesting afm wireing for similar problems, is there actualy wireing inside the afm? or only on the outside (plug to ecu)

The wiring they're talking about is the solder joints inside of the plug (afm side) where they go to the little PCB, these get old and dry and are notorious for cracking.

Running a valley cover or not is up to you, I prefer not to so it keeps the coils cooler. The igniter is earthed through the loom (look at the ECU side of the igniter, that plug should have an earth lead that pops out of the harness and earths to the rear coil cradle bolt), I bolted my igniter back to one of the valley cover bolts, works fine.

AFM dying shouldn't cause it to stall.. I thought it would just try to go into a limp mode when it cuts out.. the ECU will make a "best guess" to keep the engine running so you can limp it to a workshop..

when the AFM is toast, the ECU caps RPM limit at 2500rpm

so it is easy to pick up if the AFM is dead or wiring mangled as it wont rev past 2500rpm

what if the wires are just a bit iffy? will it work sorta? im kinda hoping its my afm...

The wiring they're talking about is the solder joints inside of the plug (afm side) where they go to the little PCB, these get old and dry and are notorious for cracking.

Running a valley cover or not is up to you, I prefer not to so it keeps the coils cooler. The igniter is earthed through the loom (look at the ECU side of the igniter, that plug should have an earth lead that pops out of the harness and earths to the rear coil cradle bolt), I bolted my igniter back to one of the valley cover bolts, works fine.

AFM dying shouldn't cause it to stall.. I thought it would just try to go into a limp mode when it cuts out.. the ECU will make a "best guess" to keep the engine running so you can limp it to a workshop..

ok well that sorta rules out the afm :domokun:

would my setup with the wastegate hose just before the bov be causing this?

ok well that sorta rules out the afm :domokun:

would my setup with the wastegate hose just before the bov be causing this?

Sounds like AFM to me. Can you solder? If not, drop around sometime, im just up the road. :laugh:

Sounds like AFM to me. Can you solder? If not, drop around sometime, im just up the road. :domokun:

haha, thanks mate, ill suss it out tonight, ill take a look inside the afm itself where the solders are, and report back, as for the actual wires, ill try fix them up a bit, (theyve been cut and connected again with solders (dont know why))

cheers

the only thing different to the last intercooler piping setup is that the actuator hose that used to come from the cooler piping just before the throttle piping and goes to the manual boost controller, is now Teed into the hose that goes from the TB to the stock BOV because the new piping dosent have anywhere for the hose to connect to.

This could be your problem. Never tee in to the pressure line for the BOV leave it on its own line. Just like you never tee a boost controller on bov on to FPR or map sensor lines. The screw with the pressure.

This could be your problem. Never tee in to the pressure line for the BOV leave it on its own line. Just like you never tee a boost controller on bov on to FPR or map sensor lines. The screw with the pressure.

i keep wondering this, but as i said, it runs fine untill warm, unless theres a second stage to car temperature that changes pressure as such?

i know its an easy fix, but ill have to drill into piping, it scares a brother haha

minor update tonight, i put the old intercooler piping back on, with the proper wastegate line, and re hooked the proper bov line, so all is as it used to be before the car was buggering up.

the car ran as normal and jerked a tiny bit but wasnt as bad, didnt stall, this was 20 mins after driving, the revs started to drop at this point and i kept violently pushing the accelorator to get the revvs back up and continued driving, this was the only time in the 30 mins i was driving that it acted up.

also, i was playing around with my dodgy afm wireing and plugs, and when i pushed down hard on the plug the car stalled, i tested this 3 times and everytime the car stalled apon pushing down on the afm plug and once when i was fiddling with the wires, so i think something iffy is happening there.

also, was bossting really dirty, major flat spot and minor poping, but not as bad as last time, this was happening above 4500 and eaver increasing as the revs rose.

i havnt yet reset the ecu the whole time, should i do this? will this fix anything? or am i hoping for the impossible?

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