spence7

Hi all - just wondering if anyone has had this prob before ? Sparks plugs are newish, then I fitted 4 new coil packs cos they were on their last legs, and as soon as I'd fitted them the first time I turned on the ignition the CEL came on.

Runs much better with the coil packs, until it gets close to full boost...when the engine just cuts out / jerks pretty harshly. Runs fine if I accelerate anywhere up to say 80% boost but when I put my foot down properly this happens. Doesn't seem RPM dependant either just boost dependant.

I've replaced the MAF sensor to no effect (well CEL stayed on but I didn't drive the car), so now I'm thinking lambda sensor - is there a problem with new coils and old lamda causing pollution problems so CEL comes on ?

Appreciate any help as I'm stumped !

Jolly Green Monster

iTrader: (4)

have you read the error code?

http://www.saxonfields.freeserve.co....iag%20Page.htm

changing the coil packs shouldn't instantly switch the CEL on so something else must have been disturbed.. unless one is not connected properly and the CEL is a misfire etc..

spence7

OK, I'll try and re-fit them to see if it makes any difference...! It's a bit odd though because it doesn't seem to be misfiring at all, not that I can tell anyway, though I guess it would be pretty obvious. It's just this fuel cut thing on peak boost

Just need to work out where those connectors are supposed to be plugged into so I can do a CEL code check...! cheers for your help

Jolly Green Monster

iTrader: (4)

Sat in the drivers seat your left knee should be not far from them.

They are usually taped back into the loom if they haven't been used before with blue / transparent tape.

Tone Loc

iTrader: (1)

What peak boost are you hiiting and what is controlling the boost (ECU, Dawes, EBC)?

Tony.

spence7

JGM, nice one I'll take a look and see if I can find them. Not sure where or what they're supposed to be plugged into though !! doh

Tony, not running anything at all.....standard filter and box, just a decat centre and Ninja BB!

spence7

Oh aye, didn't mention earlier, not sure sure what peak boost is as I have no gauge, but based on my last scooby I reckon it's over 0.8bar...cos it pulls reasonably well, but just as it reaches genuine acceleration it jerks badly as if the fuel's been shut off...

ScoobyDuck

iTrader: (1)

probably getting more 'umphh' now the sparks doing its thing...so you're spooling quicker and spiking the boost.

spence7

hmm, yeah that crossed my mind...but only have decat centre and ninja BB ? Standard filter too...but the symptoms are what you say as if there's a boost spike. Not sure if the CEL is linked to that though and they happened at the same time, but they might not be related !

dnb

The lambda sensor only puts the CEL on during a sustained cruise on the older cars. More likely you've disturbed the pipework to the MAP sensor or something.

Best of luck hunting

spence7

MAP sensor, ok I'll check that then because the CEL definately came on immediately after installing no.3 coil pack...I tried replacing just one first but as this didn't help the stuttering I replaced the other 3, this cured the stuttering but the CEL remained on.

Hmmm, so where's this MAP sensor then ?

Jolly Green Monster

iTrader: (4)

map sensor is on the inner wing between the air filter box and the suspension turret.

is black and about the size and shape of a small match box.

You need to read the error code.

There are two black plugs and two green plugs and they plug together.

I forget which is which but I think ther black are the error code so you connect them and turn the immobiliser off and turn the ignition to on without starting the car and it should flash in a sequence as described on the website I linked.

You connect all four to do the reset.

Might possibly be a fault coil pack from new then?

spence7

Pressure Sensor Duty Solenoid ! Sounds like it's linked to my boost spike issue. ! I'll check on here to see if there's anything I may have disturbed before I replace it !

spence7

Just to complete the thread for future searches on this topic:

When I replaced my coil packs I managed to disconnect the pressure feed pipe to the boost solenoid during dismantling of the airbox ! Doh ! Seems to cause the same effect as the sensor becoming faulty as I got an 45 ECU error code.

Re-connected the pipe and all is hunkey dorey - CEL gone and fuel cut / boost spike no longer a problem !

Cheers for anyone on here who said to check for disturbed pipework :-)

cheers
Alex.