Rough cold start with 35is

Ozie

Member
 Espoo, Finland
Does anyone know what's the problem in next case?

After cold starts in the morning whole car shakes a bit and the engine isn't running smooth. Sometimes there is misfire (once from 3 cyl, then 1 & 3 cyl and this morning 1 cyl). After shutdown and restart everything is fine except smoke/vapour from exhaust.

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Here's few screenshots from Carly this morning.
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My e36 coupe (m52tu 25) did this sporadically from 40k miles to 261k miles... I didnt do anything to address it.
 
That'll be fuel coming out of the exhaust. At least one injector is sticking open.

Best course of action is to replace all six. The latest revision of the injectors seems much more reliable.

Without warranty they are expensive. Proper new OEM injectors are £200 each, don't waste your time with reconditioned or old stock. It's a viable DIY job buy you need to use INPA or ISTA to register the new injector flow values so that can be a PITA if you aren't tech savvy.

If you have a warranty take it to BMW and they will have it done in a week. Just make sure you chat with the tech who is doing the work and remind him to fit the brackets/couplers to each injector as dealerships have been known to miss them out causing all sorts of odd issues (happened on my own car even after I asked them to double check after reading forum horror stories).

The injector has been dousing the cylinder with fuel causing failure to ignite thus a misfire The fuel will just wash through the exhaust system which could screw your cats up.

Part number for the latest index 12 injector is "13538616079"
 
R.E92 said:
That'll be fuel coming out of the exhaust. At least one injector is sticking open.

Best course of action is to replace all six. The latest revision of the injectors seems much more reliable.

Without warranty they are expensive. Proper new OEM injectors are £200 each, don't waste your time with reconditioned or old stock. It's a viable DIY job buy you need to use INPA or ISTA to register the new injector flow values so that can be a PITA if you aren't tech savvy.

If you have a warranty take it to BMW and they will have it done in a week. Just make sure you chat with the tech who is doing the work and remind him to fit the brackets/couplers to each injector as dealerships have been known to miss them out causing all sorts of odd issues (happened on my own car even after I asked them to double check after reading forum horror stories).

The injector has been dousing the cylinder with fuel causing failure to ignite thus a misfire The fuel will just wash through the exhaust system which could screw your cats up.

Part number for the latest index 12 injector is "13538616079"

Thanks. Already got price replacing all six injectors for 1860 € / £1580 and part number matches.
 
Ozie said:
R.E92 said:
That'll be fuel coming out of the exhaust. At least one injector is sticking open.

Best course of action is to replace all six. The latest revision of the injectors seems much more reliable.

Without warranty they are expensive. Proper new OEM injectors are £200 each, don't waste your time with reconditioned or old stock. It's a viable DIY job buy you need to use INPA or ISTA to register the new injector flow values so that can be a PITA if you aren't tech savvy.

If you have a warranty take it to BMW and they will have it done in a week. Just make sure you chat with the tech who is doing the work and remind him to fit the brackets/couplers to each injector as dealerships have been known to miss them out causing all sorts of odd issues (happened on my own car even after I asked them to double check after reading forum horror stories).

The injector has been dousing the cylinder with fuel causing failure to ignite thus a misfire The fuel will just wash through the exhaust system which could screw your cats up.

Part number for the latest index 12 injector is "13538616079"

Thanks. Already got price replacing all six injectors for 1860 € / £1580 and part number matches.

That's a reasonable price. Just make sure they know about the couplers otherwise there is potential for engine head damage.
 
Got injectors replaced and solved the problem of shaking.

Still there's problems in cold start. After hitting start button, rpm goes 2-3k and then as low as 500 before leveling to 1k and then 600. Sometimes there might be problems with some cylinders starting.

After restarting everything is fine, but again some fuel from exhaust.
 
Coils?

The fuel monitoring system on the N54 seems very reliable ..
Injectors, coils and hpfp are your main gripes..

You need some diag kit hooked up to check live readings on cold start and see if there is anything showing
 
The long crank alone makes me think HPFP. Had exactly the same, got it replaced, been one crank to start since. Flawless.
 
R.E92 said:
Ozie said:
R.E92 said:
That'll be fuel coming out of the exhaust. At least one injector is sticking open.

Best course of action is to replace all six. The latest revision of the injectors seems much more reliable.

Without warranty they are expensive. Proper new OEM injectors are £200 each, don't waste your time with reconditioned or old stock. It's a viable DIY job buy you need to use INPA or ISTA to register the new injector flow values so that can be a PITA if you aren't tech savvy.

If you have a warranty take it to BMW and they will have it done in a week. Just make sure you chat with the tech who is doing the work and remind him to fit the brackets/couplers to each injector as dealerships have been known to miss them out causing all sorts of odd issues (happened on my own car even after I asked them to double check after reading forum horror stories).

The injector has been dousing the cylinder with fuel causing failure to ignite thus a misfire The fuel will just wash through the exhaust system which could screw your cats up.

Part number for the latest index 12 injector is "13538616079"

Thanks. Already got price replacing all six injectors for 1860 € / £1580 and part number matches.

That's a reasonable price. Just make sure they know about the couplers otherwise there is potential for engine head damage.

Mine was a £2800 job but covered under Warranty. They had to replace a module as well though.
 
Again with this problem. Yesterday when I was going on a highway and gave some gas I got half engine warning light. After restarting engine all was fine, but same problems and warning light also after accelerating bit harder.

Also got few misfires earlier..

Here are error codes:

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Injectors were replaced 6 months ago. HPFP?
 

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Z4M-2006 said:
Yea,

Classic HPFP problem

Thanks. Got also new symptom... :roll:

If I try to accelerate harder car starts to "shake" bit like hitting the rev limiter. No warning lights and no fault codes. Earlier got few codes from same aymptom: Instrument Cluster shutdown A559 and Motor Control - ECU 55 "sorry, unknown DTC fault" 00DE51. I mean is this also HPFP problems or something else?
 
The HPFP sounds like its faulting and dropping pressure,under demand the fuel pressure is dropped to the injectors and misfires start to happen.
 
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