Author Topic: New engine - Rough idle cuts out?  (Read 331 times)

Offline hussnainh8

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New engine - Rough idle cuts out?
« on: March 23, 2020, 04:47:28 PM »
Hi,

Just put a BWA engine into a mk5 gti and everything was fine until I connected the airbox/MAF and the engine spluttered to death. When removing the MAF, the engine runs fine and with the MAF the engine cuts out/have to give it revs to keep it running. VCDS has given an engine code:

012600 - Intake Manifold Runner Control
P3138 - 008 - Regulation Deviation

Is this code related to why the engine doesn't stay on with the MAF sensor connected?

I have tried basic settings with VCDS in block 142 (engine) which gives me ERROR. I have tried unplugging the flap motor and reconnecting which doesn't make a difference and I have tried pushing on the rod manually and you can hear the flaps open/close manually (A bit sticky/hard) compared to trying it with the old engine. The engine runs without the MAF and sounds better than with the MAF. With the MAF the revs jump up and down and the engine eventually cuts out. Should I just replace the intake manifold with the manifold from the old engine?

Thanks.

Offline FJB

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Re: New engine - Rough idle cuts out?
« Reply #1 on: March 23, 2020, 06:02:07 PM »
I don't know if it is related to your maf issue, but if you are using a BWA engine with an AXX ecu, you either have to have the ecu updated to use the newer runner flap motor or fit an AXX runner flap motor, part number 06F133482, the revised motors with a letter at the end, "A" for example, will not work correctly without an ecu update.

Offline hussnainh8

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Re: New engine - Rough idle cuts out?
« Reply #2 on: March 23, 2020, 06:45:34 PM »
I don't know if it is related to your maf issue, but if you are using a BWA engine with an AXX ecu, you either have to have the ecu updated to use the newer runner flap motor or fit an AXX runner flap motor, part number 06F133482, the revised motors with a letter at the end, "A" for example, will not work correctly without an ecu update.

The engine i removed was a BWA and the one i put back on was also a BWA. Thanks for the advice.

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Re: New engine - Rough idle cuts out?
« Reply #3 on: March 23, 2020, 10:01:02 PM »
Is this your old maf or one that came with the new engine?
Same question on engine loom?
If you know the maf and loom we’re good before start looking for damage in the loom

Offline hussnainh8

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Re: New engine - Rough idle cuts out?
« Reply #4 on: March 23, 2020, 11:45:03 PM »
Is this your old maf or one that came with the new engine?
Same question on engine loom?
If you know the maf and loom we’re good before start looking for damage in the loom

It is the old MAF which was with the old engine, seemed to be working fine with the old engine. The engine loom came with the new engine, have checked if all connectors and pipes are on and they are, no damage to wires/plugs etc.

Could the jumping revs have anything to do with this engine code?

012600 - Intake Manifold Runner Control
P3138 - 008 - Regulation Deviation

I have tried erasing the code but it doesnt erase from memory. With the MAF connected the engine starts and with slight revs it will jump revs and die. Without the MAF it runs fine. Forgot to mention, my radiator fans stay on all the time even if the engine is cold. What is the reason for this?

Thanks.

Offline hussnainh8

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Re: New engine - Rough idle cuts out?
« Reply #5 on: March 24, 2020, 06:15:51 PM »
So today did some more diagnostics. I have tried another MAF sensor which made no difference. I have secured the intercooler boost pipes as they where leaking air (soapy water test) .. I then noticed the pcv breather hose was cracked and someone had already attempted taping the pipe back together. I got happy for a second and thought problem fixed! Replaced the breather hose to find the problem is still there.

So tried:

New MAF
PCV test (dipstick out method)
Replaced PCV breather hose (was cracked)
Intercooler pipes secured

VCDS showing basic settings aborted - mech stop. Tried basic settings and get ERROR.

Is it still likely to be the intake manifold? Is there any other hoses or sensors I could check before replacing the intake manifold?

Thanks.

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Re: New engine - Rough idle cuts out?
« Reply #6 on: March 24, 2020, 10:03:41 PM »
Do you know why the other Golf got scrapped?  - there is always a reason why they get binned.

Always best to keep all the known good items together - likelihood of troubleshooting is reduced if you know it all worked before. Loom damage can be very hard to find - my old Mk4 had a problem with the throttle body, had a pro auto electrician and a very knowledgeable mate look at it -no one could find the damage. I ended up having to rewire my throttle back to the ECU.

Try swapping the inlet over for your old known good one, if you are still having trouble, you need to swap over your old engine loom.

Offline hussnainh8

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Re: New engine - Rough idle cuts out?
« Reply #7 on: March 24, 2020, 10:23:30 PM »
Do you know why the other Golf got scrapped?  - there is always a reason why they get binned.

Always best to keep all the known good items together - likelihood of troubleshooting is reduced if you know it all worked before. Loom damage can be very hard to find - my old Mk4 had a problem with the throttle body, had a pro auto electrician and a very knowledgeable mate look at it -no one could find the damage. I ended up having to rewire my throttle back to the ECU.

Try swapping the inlet over for your old known good one, if you are still having trouble, you need to swap over your old engine loom.


No idea, the golf I have I bought from the auction, it is a cat n with airbags deployed and a hole in the sump. The engine was running without any oil and probably nearly seized itself so to be on the safe side before I resell the golf, I bought the exact same engine which came with the turbo, alternator, injectors, throttle body, intake manifold, spark plugs, coilpacks.. Pretty much came with everything except the gearbox and I thought it should be a relatively easy engine swap until this stage. I tested the engine a few days ago without the MAF sensor and it ran fine so I thought okay it should be good until yestarday when I got everything on and it was nearly time to celebrate but when connecting the MAF I started getting rough idles/cutting out.

Tbh it could be £550 wasted on an engine as there was no way to test if the engine worked before buying it so the person most likely was selling a dodgy engine to me. Now im stuck with 2 broken engines and £550 out of pocket with this very annoying issue to diagnose!

Cant really seem to think of anything else to try other than swapping the intake manifolds over now and while I am at it, I might as well change the injectors over too. If not that then I really dont know what else it could be? The engine loom seems good as in the connectors etc and im not getting any faults in VCDS other than this intake manifold runner control fault. When moving the actuator by hand, I can hear the flaps moving inside the intake manifold (with a bit of resistance) so im not sure why the error in VCDS. Its telling me the basic settings are not done for the intake manifold but when I try the basic settings instead of "ADP.OK" I am getting "ERROR". 

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Re: New engine - Rough idle cuts out?
« Reply #8 on: March 24, 2020, 10:39:39 PM »
Ah! assumed it was a car you had for a while - so you have 2 unknown engines.
BTW - Engine gets cut in an air bag deployment - your old engine may be fine

Offline hussnainh8

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Re: New engine - Rough idle cuts out?
« Reply #9 on: March 24, 2020, 11:48:14 PM »
Ah! assumed it was a car you had for a while - so you have 2 unknown engines.
BTW - Engine gets cut in an air bag deployment - your old engine may be fine

No just picked it up to repair and sell. Im not sure on the condition of the previous engine as after the accident, it must have been started up several times to load it omto the truck then to the auction then to my house etc etc and all of that time without any oil in it???? Hmmmmmm.

The good thing is I do have 2 engines and I can take parts of the old engine to put on the new engine to get the issue with the new engine fixed. Fingers crossed.

Offline hussnainh8

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Re: New engine - Rough idle cuts out?
« Reply #10 on: March 25, 2020, 06:32:06 PM »
Today replaced the intake manifold which has erased the code for the runner flap control. I now have 0 engine codes other than p0101 for the MAF sensor which I think is only because I havent actually got the MAF in the airbox. I was using it to test the car to see if the problem was fixed so I just connected it up and left it on the engine without using the airbox so the code is most likely due to this.

Update - new intake manifold, code erased but the issue is still here. The car on a cold start dies prettt much within 5 seconds. The car on a hot start can run for around 1 minute before cutting out. If i rev the car from time to time, it will stay turned on forever. But if i leave it idleing, it eventually turns itself off.

The radiator fan I have disconnected for now until this issue is resolved then i will go about repairing the fan afterwards. No other engine codes. Please help as I literally do not know what else to check...

Offline hussnainh8

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Re: New engine - Rough idle cuts out?
« Reply #11 on: March 25, 2020, 06:34:49 PM »
It must be a air, vacuum or boost leak in the system and i haven't got a smoke machine to test anything other than using soapy water which i tried 3 times and didnt see any bubbles any where.

Offline hussnainh8

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Re: New engine - Rough idle cuts out?
« Reply #12 on: March 27, 2020, 03:20:16 PM »
New engine code!

1 Fault Found:
004759 - Pressure Drop between Turbo and Throttle Valve (check D.V.!)
P1297 - 001 -
Freeze Frame:
Fault Status: 01100001
Fault Priority: 2

On a cold engine, the car does its jumping revs to 2000rpm and down to 400rpm and cuts itself out, on a hot engine it runs and you can even drive it. The engine code showing is this. If you try to erase the code, it will erase and the revs will go crazy again and car will cut itself out again, when this code is showing, the engine runs but if you erase the code the problem starts again.

Have replaced the diverter valve yestarday which made no difference. Have checked for air leaks but literally cant hear anything.. Does it need smoke testing? or is the N75 boost pressure control valve faulty? Have checked boost pressures and the actual stays at 1010 and specified is around 460 when idling. When you rev the car, the actual stays roughly the same and the specified goes up to over 1000... Could it either be a air leak or the n75 valve needs replacing? Any way to check if the n75 valve works using VCDS?

Thanks.