Cel 1275

[BlackE30]

Whats up guys, as usual another issue with my s52 swap car.

The problem started about a month ago, under full throttle hard acceleration around 4,500 rpms the car will start throwing the CEL and will start hesitating really badly like its only firing on some cylinders. Let off the throttle and its fine again. The local bmw shop did a scan and found fault codes for coils 4 and 2. They reset the codes and I drove home to look for the problem.

I pulled the coils today and checked the plugs which are brand new with less than 1,000 miles on them. Everything looked fine. Took the car out for a drive and threw a CEL under hard acceleration passing 4,xxx. Did the stomp test and it revealed 1275 which is coil number 5.

Could a crank reference sensor cause this? or a stuck vanos or something like that. I am not throwing any other codes. The coils are Bav autos that I installed about 2 years ago.

Any advice would be great.

I am having the shop install a new vanos on monday and if I don't figure anything out before then I will just have them troubleshoot it.

Jeff

[sharky]

Get a friend to loan you some OEM coils and test them out, I think thats your best bet at troubleshooting

[aeryk7]

True dont spend money on things that are def not the fix. Try to narrow things down first.

[surebimmer]

Swap coil number 5 to to cly 1. Clear FC and see if it follow's to swapped cly.

[BlackE30]

I have stock coils that I can put in to see what happens.

I'll try that first.

[TwistyTunedE30]

Are you out of gas again ;) Sorry to hear that man, wish i was there to be able to help...This is not a fun deployment. Did you ever end up getting that MAF, or the carpet i had sent to you???? MAF could be sending screwed up readings....just a thought though.

[BlackE30]

Haha, no, I have a full tank in it this time. Although the gauge is still off.

No I havent received any carpet :( I have two MAFs, both work and neither are affecting the problem. For the first time since owning this car or any car really, I think im just going to have the shop look at it.

Sorry to hear about your deployment sucking, thats no good. Should I have my mom send you some cookies?

[surebimmer]

Did you swap coils and clear the Falut code's?

[BlackE30]

I swapped the original coils back and it actually seems to have fixed the major hesitation at 4k. I'm not sure if its just a coincidence or not but I will drive it more later tonight and see if I can reproduce the issue.

The CEL lights are still there but I havent had them wiped yet. I will have Racewerks check on monday after they finish the vanos install to see if the codes flash back up.



One thing that its doing now though is it sounds like its trying to decelerate when the car is held at cruise @3,200 rpm +/- 100 rpms. Its hard to pick a word though that describes it. I would say it could also be "stuttering." The CEL flashes but there are no new codes besides the existing 1215.

More to come once it gets back from the shop.

[BlackE30]

Alright, I got the car back from Racewerks with the new vanos and gears installed. The car pulls harder and smoother than it ever has before. They wiped the codes and all was well until I was cruising at 2500 rpms and it started studdering again. CEL showed 1271. This is a strange problem. It will go away the second I let off or give it gas. It doesnt necessarily come right back either.

I have the old coils on there so I really dont think that is the problem. The plugs are new, maybe tomorrow I will swap spark plugs between one and two and have the codes wiped again to see if it comes back as 1272.

[boyd_dave]

any update on this? i have similar "stuttering".