Running Lumpy - No EML - ? - All sorted.

[Sam Mcgoo]

So Zed is running rough.

 

Car is '54 UK GT DE has 30k miles. Vortech Supercharger, DW600cc, Kinetix SSV, Uprev GT MAF, AEM basic return fuel system, etc...Uprev tune.

 

It idles ok.

If held at constant revs or constant speed it runs ok.

Any acceleration when driving or reving when stationary and it runs lumpy almost like its missing a cylinder.

I have had a bit of a tapping/rattle at a certain rev range (usually between 2000rpm and 3000 rpm) that I thought was behind the dash, but I’m now wondering if its engine side of the bulk head and possibly related.

 

Things I’ve checked -

 

Plugs look good, but changed them anyway – no change

MAF is clean as a whistle

Throttle body looks clean

Looked for boost/vacuum leaks, nothing obvious but haven’t pressure tested yet – I hope to do that when I get home next week. Vacuum at idle is about 22 inHg and it does make boost but runs rough.

AFR on bank 2 seems normal when idling and driving but I haven’t got a sensor in bank 1 so that’s unknown.

I have had a bit of a tapping/rattle that I thought was behind the dash, but I’m now wondering if its engine side of the bulk head , Changed the fuel damper on bank 2 in case it was that, but no change.

I have also, removed the S/C cog belt so running n/a but no change.

Disconnected and bypassed oil catch can, taken off vac/boost pipe from Fuel Pressure Regulator

 

 

Any ideas on where to look next?

Edited March 30, 2014 by Sam Mcgoo

[Sam Mcgoo]

Oh and maf is clean as a whistle.

[longsh07]

Have your checked the throttle body? When I had a lumpy idle turned out to be just a load of crap on the butterfly which was cleaned off with some carb cleaner and a cloth.

I understand its not recommended you move butterfly however I did on mine (only a small amount to wipe around the point at which it met the throttle housing) then did an ECU, throttle pedal position and throttle position reset and never had any issues since.

[Sam Mcgoo]

Thanks for the suggestion. I did have a look at it and it was actually very clean, so didn't think it was worth disturbing.

 

Also, it's worse through the revs than it is at idle.

[longsh07]

No, not worth it if its clean.

Wouldn't know where else begin looking on a supercharged zed

Good luck, hope you can get it sorted

[Tricky-Ricky]

Have you still got the evap control solenoid fitted? check that's working and there are no leaks.

[Sam Mcgoo]

Have you still got the evap control solenoid fitted? check that's working and there are no leaks.

 

Thanks for the input.

 

Yeah I believe I have. Not heard of any issues with that before, what makes you suggest that?

[Sam Mcgoo]

First post edited with a bit more info.

 

Anyone know the best way to do a DIY boost/vac test? I was thinking of getting some bungs for the exhaust and inlet and using a pump to pressurise the inlet manifold and soapy water around all joints, hoses ect...

 

Anyone done anything similar?

 

Also gonna get another coil pack to try swapping them out one at a time to eliminate one of them breaking down under load.

[GT4 Zed]

Difficult one to say but you are doing the right checks.

Go methodically and you'll hit the spot.

 

Just go round all the hose clamps tighthen/swap them iff loose or worm gear burred.

the do a TB and idle volume reset.

Check for any exhaust leaks especially up stream eg y-pipe cats flange.

If no joy then do a compression test. You can get a kit and DIY. If there is any abnormality the pay for a leak down test.

I take it the car is not smoky at idle or under load and not consuming oil. Does the car still pull or is it out of puff?

Good luck and let us know how you get on.

 

 

[GMballistic]

I would suggest you

First post edited with a bit more info.

 

Anyone know the best way to do a DIY boost/vac test? I was thinking of getting some bungs for the exhaust and inlet and using a pump to pressurise the inlet manifold and soapy water around all joints, hoses ect...

 

Anyone done anything similar?

 

Also gonna get another coil pack to try swapping them out one at a time to eliminate one of them breaking down under load.

This is what I was going to suggest you try.

Literally just had a similar sounding problem with my DE mis-firing & traced it to a faulty coil pack. Replaced it and it's running great now.

[rothers2901]

What about a faulty coil pack, high resistance when under load?

[Sam Mcgoo]

Difficult one to say but you are doing the right checks.

Go methodically and you'll hit the spot.

 

Just go round all the hose clamps tighthen/swap them iff loose or worm gear burred.

the do a TB and idle volume reset.

Check for any exhaust leaks especially up stream eg y-pipe cats flange.

If no joy then do a compression test. You can get a kit and DIY. If there is any abnormality the pay for a leak down test.

I take it the car is not smoky at idle or under load and not consuming oil. Does the car still pull or is it out of puff?

Good luck and let us know how you get on.

 

Cheers Bennett, Na no smoke, and never drinks any oil. Its definitely down on power, any accelerating at all and it feels flat and sounds rough.

I do have a compression tester and will do that along with the inlet leak test and coil pack swap out.

Haven't done the TB or idle resets either.

 

I would suggest you

 

Also gonna get another coil pack to try swapping them out one at a time to eliminate one of them breaking down under load.

 

This is what I was going to suggest you try.

Literally just had a similar sounding problem with my DE mis-firing & traced it to a faulty coil pack. Replaced it and it's running great now.

What about a faulty coil pack, high resistance when under load?

 

As above, will try swapping them out one at a time with another. I have tested them all at the connector and all read the same, however, I assume the connectors aren't directly connected to the coil and go through some sort of circuit. Also they are not under load when tested.

[Sam Mcgoo]

Update -

 

I leak tested my intake and hoses etc and found a couple of issues -

 

 

 

 

The first one could be a gasket issue, but the second two looks like the welds have given up after too many heat cycles maybe. The one on top is just a pin hole and the one at the boss seems like a small crack.

 

They are not massive leaks, but using a tyre inflater to pressurise the plenum It won't hold more than 10psi and within 5 seconds of turning it off the pressure has gone.

I don't know how long they've been there, so don't know if its my only issue but it's one I must address first.

 

I just hope the leaks haven't been there for some time, and maybe caused it to run lean causing more serious issues.

 

Now do I get my lovely blingy plenum re-welded....or put a stock one on for now.......

[hensh65]

Glad to see you are getting to the bottom of this, nothing worth than having an issue with your car. Even worse when you don't know exactly what the issue is! I would suggest going for the stock plenum if you aren't 100% this is the root cause of the issue

[R35LEE]

Getting there then Sam

[Wasso]

Sam isn't the Kinetix highly prone to blowing welds especially when boosted. The Cosworth is the preferred boosted per the US. I'd take it off repair it sell it and replace to be honest.

 

Don't you just hate it when trying to identify problems. I've had my fair share of this also.

[ZMANALEX]

Bin the Kinetix and stick on a Cosworth.

 

I had the same issue with Kinetix and rewelded it all the way round, however it is so thin that you could shoot peas through it.

 

Alex.

[Sam Mcgoo]

Further update -

 

I haven't got round to getting the plenum leaks welded up yet, and although they do need sorting I wasn't convinced its the cause of my issues so decided to do a bit more fault finding.

 

Chris (Keyser) VERY KINDLY lent me a coil pack and a pair of VVT controllers to help me eliminate them as potential causes.

 

So one by one I swapped out the coil packs thinking it would probably be the issue......No change

 

I then tried the VVT controllers ......again no change .

 

During all this, I noticed that one of my true dual exhausts was smoking more than the other and it was this one that seemed to be spluttering. This obviously concerned me.

The car never uses any fluids, ever, so thought it was unlikely a head gasket or anything more serious but decided to do a compression test anyway.

 

The first good news - Compression test was good. see bottom row below.

 

 

 

I then looked at the plugs I just pulled. Five of which were black as the ace of spades and one was not. These have only been in for a short amount of time since I had the issue.

 

Plugs from Cylinders 2,4,6,

 

 

and 1,3,5

 

 

This suggested that cylinder 1 may be running lean and all other cylinders were being run rich to compensate.

 

I looked at the plugs I removed when I first started getting the issue (not anywhere near as bad then) and although they looked pretty normal on the whole, it can be seen there are signs of number 1 running slightly leaner than the rest.

 

2,4,6

 

 

and 1,3,5

 

 

 

I then connected my OBD2 reader and loaded Torque up on the phone. No fault codes were present as before, but it could be seen that the ecu fuel trims were adding about +4 to 6% to bank one but removing - 7 to 9% to bank 2.

This again suggested that bank 1 (cyl 1,3,5) was not getting the same amount of fuel as bank 2 (2,4,6).

 

I'm now thinking an injector problem. Surely not, they're only two years old and covered about 10k miles. And after having faulty/ out of flow tolerance ones on my previous second hand set prior to that??

 

 

I decided to remove the injectors, coils tested ok for resistance and functioned when given 12v.

I marked them up and put them back in the opposite banks. Once all back together I fired it up, and as suspected the smoke, popping and fault swapped to the other bank. The fuel trims were also opposite to before. Finally getting somewhere now.

 

I suspected the issue was with the injector now fitted to cyl 2. I had a spare injector from my previous set and although not flow matched with the others, I figured that it was worth a try.

 

After swapping the injector with a spare - It purrs like a kitten Haven't had a chance to go for a drive yet but idles and revs fine. Also the fuel trims are pretty even and now both +ve figures.

 

So I'll go for a drive tomorrow and see how it is.

 

I must say I'm pretty dissapointed that I potentially have another faulty DW600 injector. I will try and get them cleaned and tested first but not holding my breath.

[R35LEE]

Glad u traced the fault pal now I guess you should get that plenum welded up

 

Sent from my HTC One using Tapatalk

 

 

[HARMLU]

Glad you got it sorted nothing worse than not knowing the fault.

 

A good write up for anybody who may encounter similar problems in the future

[evilscorp]

Do dw have a warranty? Or can you send them away for repair/cleaning? (Got me paranoid now lol). At least you also found that the kitentics is holding your baby back too.

[Dblock]

Sorry to hear your having problems but the way your solving them is good reading/information

[Sam Mcgoo]

Do dw have a warranty? Or can you send them away for repair/cleaning? (Got me paranoid now lol). At least you also found that the kitentics is holding your baby back too.

 

12 months I think.

The last set I had trouble with a couple of years ago, Abbey cleaned and flow tested them for me but one of them was massively under supplying.

I sent them back to Deatchwerks for servicing. They contacted me saying that I would need to replace 3 of them to make a propper balanced set so I did.

 

I might try just getting these cleaned and tested again and go from there.

[Sam Mcgoo]

Sorry to hear your having problems but the way your solving them is good reading/information

 

Cheers, I thought it best to try and be thorough, as I struggled to find anything to help me when googling this problem. Most faults have a CEL to point you in the right direction.

[GT4 Zed]

Sam that is proper diagnostic trouble shooting and I'm so relieved for you that it was not anything major! Nissan would have been clueless!

I had a little scare myself starting my car after it been at RTP for some much needed cosmetic work.

It was really rough and power was way off. I suspected either a small boost leak in case the pipes may have been moved during taking the bumper off or a dirty MAF or TB as fibre glass/ filler/paint laden dust gathers in the body shop amazingly.

Quick check of IC pipes, vacuum hoses etc was fine so removed the MAF and it was then MAF check and it was coated with a crust of dust! After multiple blast with electrical cleaner it was clean as a whistle and the car runs perfect with the rumble of the new exhaust. Didn't bother to clean the TB but will later as part if my big start of year service.

 

BTW what Kinetix do you have? I know the SSV V1 had issues which was addressed with the V2 that I have. The welds are solid so I'm curious.