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OK so i brought the car 3 or 4 weeks ago now and since then i have noticed a hard to start problem...

I thought it may have been the coolant temp sensor so replaced that, and still no luck unfortunately :D

It doesnt do it all the time, if i start the car in the morning when it is cold outside it will start fine but the idle will hunt and i will have

to give it some throttle to prevent it from just die'ing in the ass. But if i leave it say 30 mins after i stop and goto start the car it will

crank for between 5-10 seconds before it starts, and it will do this regardless of whether i hold my foot on the accelerator or not. So

it actually does this even when the engine is warm, but if i stop the car and try to start it straight away it will start fine, which makes

it hard to diagnose. Throttle body, injectors etc etc have been cleaned, i was going to clean the AAC valve but didnt really think that

would be the problem since it makes no difference if i give it some throttle when starting... Maybe i have a leaking injector? or are

their any other problems i should look into?

Thanks, Adam.

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OK so me and a mate pulled them out and i got them all overhauled with new seals and caps etc etc and bench cleaned and put them back in thinking i have solved the problem and it still f*cking does it, driving me nuts i am completely out of ideas and dont know what to do, when i crank it it jus DOES NOT want to start for 4 or 5 seconds then fires. I am thinking it is probly losing fuel pressure somewhere? maybe fuel pressure reg ? PLZ help sum1 ??

not a pro but i have a suggestion... fuel pump, clogged fuel filter, or your not getting enough spark. if it was the coolant sensor your car would idle high and not come down cause the comp would assume the engine was cold. maybe some new plugs (they could be caked in oil and the previous owner just *forgot* to mention it) and fuel filters are a cheap part to throw at it.

not a pro but i have a suggestion... fuel pump, clogged fuel filter, or your not getting enough spark. if it was the coolant sensor your car would idle high and not come down cause the comp would assume the engine was cold. maybe some new plugs (they could be caked in oil and the previous owner just *forgot* to mention it) and fuel filters are a cheap part to throw at it. You should just buy one of our cars lol.

not a pro but i have a suggestion... fuel pump, clogged fuel filter, or your not getting enough spark. if it was the coolant sensor your car would idle high and not come down cause the comp would assume the engine was cold. maybe some new plugs (they could be caked in oil and the previous owner just *forgot* to mention it) and fuel filters are a cheap part to throw at it. You should just buy one of our cars lol.

Check for exhaust manifold leaks due to exhaust nuts that are not tightened up properly on turbo to exhaust

manifold joint. Or lose nuts / broken studs on the exhaust manifold itself (common problem with RB motor).

Also check for a sticky IACV valve. IACV valve is located on top of bottom of intake plenum, just

behind throttle body when looking from front of car. Clean and readjust the valve. If there's still

a starting problem after cleaning valve, replace it.

Fuel filter in engine bay or sock (filter) on fuelpump would be next area to look at. Fuel pressure can be checked

by plumbing in a fuel pressure gauge between I think is fuel regulator, fuel filter.

Edited by SKYPER

Has a bosch 040 fuel pump recently fitted well about a year or 2 ago i do rememba see'ing the receipt, it has injector pulse, set of new spark plugs, coilpacks look fine their were no cracks in them they actually looked quite new so i dont think its a spark problem, it makes no difference whether i prime the fuel pump or not. Maybe i am looking at an electrical fault like fuel pump relay or something ??

If car has a bigger aftermarket fuelpump, engine probably will be running rich. You'll need to retune stock ECU

or buy a aftermarket ECU.

Bosch 040 seems to be a 300lph fuelpump, which is probably suited to 6 x 720cc injectors -

http://www.boschfuelpumps.com/

I think stock R32 GTR fuelpump is 195lph and R32 GTS-T is 135lph. So the 040 sounds like a bigger fuelpump than stock R32 GTS-T.

Edited by SKYPER

oh ok, timing belt replaced 400 km's ago along with water pump and all drive belts. The problem was there before we did them so yeh thats not the cause of the problem. it runs lean on start-up though so its asif its not getting enough fuel, i have replaced the coolant temp sensor as that was the first assumption, then a couple of days ago i soldered a resistor in the yellow wire coming off the coolant temp sensor so it would run abit richer, then started it up and it was running way too rich. Should i be looking towards an electrical problem maybe? like a fuel pump relay or something...?

I think there is a electrical trick you have to do to with Bosch fuel pump.

Not sure, but I think it might have been to do with the voltage the pump receives.

Here's a thread about installing Bosch fuelpump in R32 GTS-T -

http://www.skylinesaustralia.com/forums/In...html&hl=040

Edited by SKYPER

Check the engine temp sensor.

Then check the ECU

The ECU can tell you where something is not working or you mechanic can do a diagnostics on it to see where the fault lies.

It sounds like a fueling issue.

I am priming the pump, not that stupid lol... and i thought it could have been an immobiliser issue due to a dodgy install but its been pulled out now and still the same problem so that eliminates that. Could a coilpack be causing this issue...? just out of curiosity. Also i have replaced the coolant temp sensor that was the first thing i thought it may have been. And injectors have new seals and caps etc and have been tested and cleaned and they are fine, we tested and their is injector pulse when i am cranking it and it doesnt fire so im definately thinking it is a fuel issue. Just put a new set of plugs in it too

Could also be low battery cranking amps... could try hooking up another battery first thing in the morning to see if it starts right up. My car had that problem after giving a jump to a commodore. Even though it seems to be cranking good enough, the battery could be dying in the arse a bit to make the difference.

  • 5 months later...
fouled up plugs from running too rich which may give less spark thus making the engine hard to start?

hi mate, i have the exact same problem and i have tried all of the above with no change. i have also done a FPR and raised it way up to see if there is a change. ive swaped both the cold start valve and the idle valve. its been a year and still no solution. ill watch this thread and add new things i have tried to help solve this problem.

let me guess it boosts up real good drives fine but its a dog when its cold and when you drive it like a pussy?

Hmm. Well its hard to start. When it does start it misfires for a while. After that it all runs good, doesn't matter how you drive.

i just think to solve my problem is a re-tune for the power fc, I've tried changing cold start switch and doesn't make a difference.

Also tried retarding the timing and no difference.

Well its getting annoying, people think you have a dead battery or your cars just screwed and give you funny looks. LOL.

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