Advice please

[heathy325]

Am just fuming to the end of the m52 conversion and got a running isue I'll give you some background first, engine was removed by myself from a running 328i in December I've done the m50 manifold conversion it's got a Danthe loom complete with ecu ( ews removed and the mapped for the m50) the car starts ok sometimes but every now and again it's slow to fire and has a bit of a backfire it idles fine, smooth as you like, but when you open the throttle it's like it's got a misfire, sounds lumpy!! Have done the brake cleaner round all the inlet and pipe work, which is fine no leaks checked all connections and fuel feed but still the same, any ideas? I think it could be the crank sensor but just want advice first if someone has had this too cheers

[rich318i]

you tried the oil cap trick ? undo the cap and see if the engine sounds any different for about a sec or 2 of not and sounds the same check the rocker cover rubbers or the cover has cracked.

Do you know someone with a smoke machine tester?

More to be the cam sensor if no leaks. My mates one fired up really horribly sounded the engine was running backwards at startup but once started it was fine. Now new cam sensor and all good!!

[heathy325]

Don't have a smoke machine tester but I have noticed there's a lot of condensation cumin gout the exhaust but I thought these were like that anyway and the rockercover gaskets are new and there's no cracks?

[rich318i]

you losing water? shouldn't have condensation this time of year..

Head gasket or maybe worse cracked head or block

[Brianmoooore]

Get it hooked up to a diagnostics computer. INPA or DIS.

[heathy325]

Nope water is bob on filled it up when installed and haven't used a drop, also was pressure tested and compression tested before it went in the car too, I've run a diagnostic check but nothing unteward flashed up apart from crankshaft sensor but I figured that was because I had just unplugged the sensor

[rich318i]

Cam sensor NOT CRANK!!! my moneys on

No Miss fire codes?

[heathy325]

I'll give it a go! Cheers

[rich318i]

just check the plugs aswell might be that simple

where are you based mate?

[heathy325]

Nope no misfire codes just got one O2 code for bank 4/5/6 but hasent showed again

[heathy325]

Don't think you can get them mixed up can you? Will they plug into the wrong ones?

[rich318i]

what way round are your O2 sensors on the loom?

They both fit in both plugs easy mistake to make

Rear bank to the front plug and front bank to the rear plug

[heathy325]

Ye Danthe said that about the O2 ones so there defo right way round

[rich318i]

where are you based?

[heathy325]

Preston just off jct 29

[DanThe]

If your getting a crank sensor error then thats the first thing to look at, it wont show an error from being unplugged unless you unplugged it while the engine was running.

[heathy325]

Ye it hasent been run with it unplugged so that's why I thought it possibly the sensor so ill swap that first cheers

[DanThe]

Dont buy an aftermarket/cheap unbranded sensor, they are shite and last weeks if that

[heathy325]

The Eurocarparts ones any good? There's two types one cheep and one more expensive? (Pwm I think)

[rich318i]

Brand names only!!! like BOSCH, which are OEM

[DanThe]

Siemens is the OEM not Bosch

These are over £100 from BMW now, there are some Delphi listed on ebay at £55 which is a decent brand name, but id rather run a genuine second hand sensor

[heathy325]

Do you have any dan? Cheers for the exhaust connector too worked a treat

[rich318i]

siemens and bosch are Dan. My coil packs say bosch crank and cam sensors say bosch im sure. depends on the ECU maker at the time

All the same people anyway

[heathy325]

As suspected it was a crank sensor fitted it and runs like a dream

[rich318i]

Nice one