Paulgeorge01

Hi All a bit of help & advice please if possible.

MY99 UK Classic Turbo V5, first of EJ205 rear thrust engines. Car is standard apart from decat downpipe & stainless system from cat back (ECU in original state). The engine ran & idled fine with this system in place prior to these problems. Once up to temp the car always idled like a Swiss watch at 750 rpm constant with no fluctuation, engine never missed a beat.

High Idle: When I start the car from cold the revs will shoot up to about 1800 rpm & immediately drop to a lumpy idle hunting between 1350 to 1450 rpm. When the car is up to temperature the idle rpm will increase slightly & idle lumpy between 1450 to 1550 rpm.

On driving the car, every time I dip the clutch to change gear the revs will shoot up about 300 to 400 rpm as if I had kept my foot on the accelerator slightly when changing gear. After say a few miles driving I will stop at a junction, when I disengage the clutch plate at standstill the revs will shoot up to about 2100 rpm dropping back over about 5 or 6 seconds to 1650 to 1750 rpm & hunt between that higher ranges as long as I stay still.

Jerkiness/juddering under acceleration:I can only quote what is happening up to the 3000 rpm rev range as I’m only roughly 500 miles into a 1000 mile running in process after a complete engine rebuild which makes these problems a bit of a nightmare in regards to heating up & cooling down engine prior to & after driving & also the damage the acceleration issue can cause (mixture to combustion bores). I have just spent a lot of money on rebuild so I really need to get this fixed ASAP. In every gear whether it is very light acceleration (driving Miss Daisy) or normal acceleration (not fast acceleration) the car judders/jerks around temporarily losing & then regaining forward thrust. Add this to the idle problem & driving my classic is not a good place to be especially for running it in too.

When not accelerating, driving at say a steady 60 mph in top gear the car is really smooth like you would expect from a newly built engine, it doesn’t go pear shape until you push the clutch or accelerator pedal.


On treble checking everything I noticed I had a small tear in the turbo intake pipe where it goes onto the turbo intake nipple around the jubilee clip area. I whipped off the inlet manifold, changed out the pipe, fitted new OEM gaskets & torqued inlet manifold down to 25 nm, buttoned up the rest. Started the car; still had both issues.

The idling issue is not just ECU relearning after reset which on my car only takes about 30 miles or so during which time my car does idle high once up to temp, is this normal for the car to go through this learning process after every ECU reset? I have heard conflicting information on this subject? I know with my car every time I have had the battery disconnected for work over the years the car always went through a learning process for about 30 miles which always resulted in a 1500 rpm idle once up to temp but then after 30 miles or so the engine reverted back to normal mode & a normal idle speed of 750 rpm was rock solid once more. This time it is different, the parameters are different & also the problem still persists after 100 plus miles & counting. I was hoping the idle problem would go away after ECU reset but it didn’t. I have only driven the car the 100 plus miles to see it would disappear. Don’t want to drive my car anymore in case I damage it after all the money I have recently spent. Here is what I’ve done to date to troubleshoot these problems. Note I still have no CEL light.

Changed maf for brand new OEM V3 (best one for my car), checked position of butterfly valve in throttle body with accelerator cable fitted – valve is shut. With car running checked the throttle cable was not under tension holding the butterfly valve slightly open causing the higher idle rpm.

Cleaned IACV & refitted – no success. Installed one temporarily which I just took off 5 minutes earlier from the exact same model of turbo (same part) that was idling spot on – no success so rules that out so refitted my one.

Have reset ECU multiple times using both methods – no success & still no visible CEL light.

Fitted new OEM fuel & air filters & turbo intake pipe.

Checked all pipe work & vac hoses from manifold. Checked & flushed boost solenoid & pressure exchange solenoids & hoses with carburettor cleaner. Checked intercooler, Y pipe, recirculating dump valve pipe, checked PCV hoses. Checked condition of all sensors & connectors & wiring – no visible problems.


Fitted new magnecor HT leads, plugs have only 12,000 miles (laser iridium & gapped as per spec, also car ran fine with these plugs before). With car running checked fuel lines from tank, through nearside of car, through bulkhead to engine bay & onto injectors – no visible leaks. When inlet manifold was off checked fuel crossover pipework under inlet manifold, hoses & clamps - looks fine. Any help would be greatly appreciated. Getting a bit worried now & am now without a car until I get this fixed, nightmare

Cheers Paul.

popeye540

iTrader: (5)

Hi bud just read a guys post a couple down from yours he's had the same jerking as yourself in the same rev range it was an O2 sensor with no cell on might be worth a check

Paulgeorge01

Thanks for your reply Popeye, much appreciated.

Am going to breakers on Wednesday with car as luckily they have one in. Am going to have a parts swap fest & will add the 02 Lambda to my long list.

Cheers Paul.

popeye540

iTrader: (5)

Hope you sort it bud nothing more annoying if you can't see the prob

Paulgeorge01

Very true.

Cheers Paul.

aaron_ions

I have also had very similar to this on a v6 uk turbo. Changed intake pipe, inlet manifold gaskets, vac hoses to rule out air leaks. Changed everything on the turbo side.. Intercooler, boost hoses, dump valve. Various sensors... Crank, knock, maf, boost sol, manifold pressure sensore. Tried a diff ecu. Was drivg me mad cos the way it was running was more like an air leak lol. But after about a month of crap running it finally threw a CEL and ended up being the o2 sensor. Changed it today infact and now the whole cars like new again. Jerkyness, bad idle, jerk/flat between changes etc are all history... For now! Hope u sort it mate.

Paulgeorge01

Glad to hear you got it sorted Aaron.

Unfortunately changing the lambda 02 didn't fix my problem.

Am going to start another thread now as going into different things.

Thanks for all the help. Cheers Paul.

kevo10

Have you taken the throttle body off, and give it a good clean. Certainly helped mine.

Paulgeorge01

Thanks for the reply Kevo.

I have a new inlet manifold pcv valve & throttle body gasket in the post from ICP as I type. Picked up some throttle body cleaner so plan to do this & a few other jobs over the weekend to try & get to the back of my problems.

Cheers Paul.

Steve Whitehorn

iTrader: (13)

Let us know how you get on Paul
I really hope this fixes the problem for you
Fingers crossed mate

Paulgeorge01

Thanks Steve,

Hope all is well with you mate.

Have started a new thread for this problem as I'm now going into other area's of trouble shooting.

See link below to follow progress. Under this link I have also done/added some additional trouble shooting over & above what I've done in this thread.

https://www.scoobynet.com/engine-man...on-sensor.html

Over the weekend hope to get a chance to mess around with adjusting the voltage on the TPS on my original, I also have another TPS complete on throttle body which has the elongated adjustment screws rusted in position (removed myself from local breaker), this will obviously provide a good second option for back up - ordered new throttle body gasket just in case along with new inlet manifold pcv valve just in case my one is sticking open & not working as should be on differential pressure.

If no success on this then I will order up a vac gauge & check manifold vacuum pressure is behaving as should as per factory spec & a fuel pressure gauge to check system within correct parameters & correct operation of the fuel pressure regulator & vacuum hose that operates it from inlet manifold.

One of these days I might get it fixed & get the old girl back on the road. One of these days mate.

As always Steve much appreciated.

P.S. After seeing your email I am definitely jealous, what a beast!!! you have done some job there mate.

Davec30

iTrader: (2)

I had this problem. Turned out to be the coil pack. Changed it for a secondhand one, went for a drive and no jerking no rough idle and it's been fine ever since.

Hope you get it sorted.

Dave

Paulgeorge01

Thanks for the reply Dave, much appreciated.


See below as have now rectified the problem


Cheers Paul.

Paulgeorge01

Hi All,

BIG!!! thanks for all the help.

Problem solved, it was indeed the TPS that was causing all the trouble.

Set up TPS & the car is now running & idling bang on the money.

Roll on another 200 miles so I can drop the Millers competition mineral running in oil & the jdm black filter & get in the Millers competition fully synthetic triple ester & new jdm black filter & see if the old girl has still got some legs about her


Am chuffed to bits.


Cheers Paul.

Steve Whitehorn

iTrader: (13)

Well done Paul
I am glad you got to the bottom of it, after all our emails


This stuff is better than Ester Sythetic for an Impreza
https://www.facebook.com/Silverlineukltd
The chap is called Ray and if you call him he will explain the technicalities of why

Paulgeorge01

Hi Steve,


I cannot thank you enough for all the help & email correspondence.


You are a true star, it is people like you who make these forums what they are. In modem day society we are so wrapped up in out busy life's that we sometimes forgot to take the time out to help each other. It is people like you Steve who set an example & remind us of this.


Thanks again mate, will definitely check out the information on the oil.


Cheers Paul.