Style

iTrader: (1)

as above, on accelerating getting a jerking and from reading many threads sounds like it could be cause my oil is too high. think i had it filled to the hole, above the top (full) nontch on the dipstick, so too much oil in it. how / wgere abouts is the boost solenoid to clean it?

is it on the drivers pillar? and is carb cleaner going to be alright to use, or do i need something else

scoobian

brake cleaner or carb cleaner is wot Ive used without any problems

myblackwrx

iTrader: (1)

Driver side suspension turret just above my IK

Take off the pipes (remember where they go plug the green connectors under the dash togther DON'T TURN ON THE ENGINE just leave on full ignition this puts the solenoid in test mode so it goes through it's opening/closing sequence.

think you will get best results spraying into the top hole.

dan83590

I second that MBWRX. The important bit is to connect the green connectors and get the solenoid clicking as you spray..

Why do you think it needs cleaning, did you over fill the oil by quite a bit? You say it is jerking, how bad is it and how does it happen?

Style

iTrader: (1)

hi, tried giving it all a good clean, and the pipes, still get some jerking. the thing is it was slightly overfilled back in october, but only recently started jerking. what happens is, it will mostly do it in 5th, and 3rd. if i even go slightly onto boost at low revs, im getting quite a bit of jerking like its trying to cut out.

when i came off a roundabout yesterday changing up through the gears, 3rd gear came on all juddery, and wasnt a clean smooth bit of boost, was hestitant ans jerky till i eased off accelerator. not sure what this could be..

any ideas, got a FMIC to fit shortly and get a remap, but cant really do anything till i get this jerking stopped

slipstream_uk

iTrader: (1)

1.Connect the green plugs and turn on the ignition (dont start engine)

2. The solenoid should start pulsing / clicking

3. Remove the top pipe and squirt brake cleaner in, then re-fit hose.

4. If it still plays up then it is probably worth removing all the hoses that attach to it and cleaning them out aswell.

5. Turn off ignition and disconnect green plugs







The green plugs are up behind the steering wheel

dan83590

Of course if you have a boost controller of some description fitted all of the above comments by myself and others are completely irrelevant!!

What mods does this car have? Could the boost be set too high?

Edit: The green connectors can be a pig to find if they have not been used before. If you struggle to find find them remove the surround below the steering wheel and hunt higher..

Style

iTrader: (1)

hi, yea cheers, they awere right up there and pretty hard to find!

got them connected and removed all the pipes sprayed them out clean, and sprayed the solenoid as it was clicking away.

it definatyely did seem better, but still does it bit. could the placers where the other ends of the pipes connect still be slightly blocked? is it gona be worth taking the tubo etc off and giving them some carb cleaner? pain to take turbo right off, can i do it still connected?

dan83590

A few questions for you to answer.

What year and model?
What modifications?
Do you have a boost gauge, if so what is it reading when the jerking happens?
Does it jerk at full throttle or part throttle?
At what revs does it happen?

Answer as many of these as you can and we should point you in the right direction..

Style

iTrader: (1)

ok cheers.

right is a 1995 wrx import, 3" dowqnpipe back exhaust, other than that standard,

have got a HKS f conS ecu ive had fitted for past month or so without any problems, is supposed to be mapped for my car with exhaust and induction kit.


yes have a boost gauge, happens at full throttle at low or just starting to boost point. if i give it full throttle at around 2 - 2.5 k in a high gear i know i will be able to get some jerking as it starts to try and go on boost.

I have also got standard ported headers

dan83590

Definitely sounds like overboost.

Does the car have a Manual Boost Controller or an Electronic Boost Controller? Turn it down until the overboost stops and have a garage double check the AFR and tweak the ECU map.

Is the ECU mapped to suit your car with your mods? If so I'd go back to where it was mapped ask them to tweak it.

Have you taken the ECU from another car and plugged it into your car? Then it needs to be set up and mapped for your car.

MrNoisy

iTrader: (28)

Had a similar sounding problem to you - was one of my spark plugs needed replacing - changed it over - problem solved.
One more thing to try I guess - you never know - might not be oil-related.

Style

iTrader: (1)

have disconnected the F CON, back on the old z4, which is going really well, but using a lot more fuel. now i dont get the problem as muchnow, only in 5th.

happened this morning giving it some boost in 5th, then dropping to about zer(no boost) for a little bit then going back on boost the car was really hesitant, and wouldnt accelerate no matterr how far i put my foot down. the further i put my foot the more it felt like it was gona cut out. i dropped down to 4th and gave it some, it boosted on well, then changed up to 5th and it carried on boosting with no problems.

Just seemed to be when i was accelerating really gently, then put my foot down to go on boost in 5th

dan83590

It will only reach its full boost on full throttle in fifth. The extra fuel used will be down to the different map on the Z4 ECU.

dan83590

I don't know if anything will show up but it might be worth reading the ECU for fault codes whilst the original ECU is in.

Look here JollyGreenMonster.co.uk

Are the vacuum pipes from the map sensor and boost solenoid all standard?
Are the pipes all fitted correctly and cable tied on?
Now the Z4 is in what does it boost to in 5th?

Or, you could just fit a dawes valve and bypass the problem!! Up to you, if it were me I'd be bugged until I'd found the problem and fixed it.

Style

iTrader: (1)

yea im same, it is really bugging me! yea they are all the same but not cable tied since i removed them.

i do have a turbosmart manual boost controller i was gona fit about a week ago. - so that might sort the problem?

and whats the best way to fit it? its adjustable by the *** on the top, do you wana turn it right down, take it for a drive, and keep turning it up till its about 1 bar or 1.1 then lock it in place?

seems to boost still to just under 9000rpm back on the Z4

where do i wana fit the boost controller? from the small tube coming off the Intercooler pipework going to the boost solenoid? currently i have a small black plastic reducer in place. - remove it and fit it here?

dan83590

I dunno. Is that one a bleed valve? Bleed valves are the worst of all the manual controllers. I'd stick with the tried and tested Dawe Devices from 3barracing.

Your Z4 will hit fuel cut before 1.1 bar. See the quote above. Set it at the standard boost for a Z4 and goto a tuner and get it set up, or at least monitor the air/fuel ratio yourself if you want to go higher, to be on the safe side.

I'm not sure how much more boost you could pinch with the Z4, some run up to 1.1 bar with a fuel cut defender.

As you have an F-CON ECU why don't you fit your mods and then go get the lot mapped properly. It'll be much better than a Z4 ECU once mapped.

Style

iTrader: (1)

ok yea will do that, got a fmic, walboro and gona get some better injectors when i get it mapped

myblackwrx

iTrader: (1)

Errrr you sure

dan83590

And in the meantime whack a dawes on to make the car drivable. Set it to 0.9 - 1.0 bar, should be fine. The dawes simply replaces the Boost Solenoid (pipes A and B in the picture above).

**dan83590 industries cannot be held responsible for irresponsible usage of boost**

dan83590

Oh forgot to say... Leave the boost solenoid plugged in or the ecu will bring up a cel.