Odd e36 problem with the engine / MAF / Cold start

[Denjeesi]

Hello,

So it was getting colder here in Luxembourg the last days (about 3 degrees Celsius) and didn't drive the car, today I started it and it was bogging and almost stalled at idle, I think it was misfiring, but as soon as I drove for about 1 minute it was completely fine again.

I opened the hood to see what was wrong, I randomly unplugged the MAF and it didn't change anything! The car runs exactly the same with or without the MAF unplugged, so is the MAF bad?

Can anybody help me? Is the cold temperature idle problem related to the MAF not working?

Also I forgot to mention that last night I had the battery unplugged.

Thanks

[Beer+Oversteer]

Could be a few things, I actually have the same issue on one of my cars as well. Very erratic cold start and it does stall out if its super cold. One thing it could be is an intake leak. I've gone through my whole intake manifold a few times, taking out the ICV and cleaning it but i had the same symptoms. It could be that the DME needs to adapt to the new air temperatures considering it may have reset adaptations if it sat without a battery charge. It could be a crank position sensor, it could be a dead MAF in your case. Are you getting any check engine codes? Does the car run normally once its hot?

[Eric93se]

Run a bottle of injector cleaner, smoke test for vacuum leaks.

[Denjeesi]

Could be a few things, I actually have the same issue on one of my cars as well. Very erratic cold start and it does stall out if its super cold. One thing it could be is an intake leak. I've gone through my whole intake manifold a few times, taking out the ICV and cleaning it but i had the same symptoms. It could be that the DME needs to adapt to the new air temperatures considering it may have reset adaptations if it sat without a battery charge. It could be a crank position sensor, it could be a dead MAF in your case. Are you getting any check engine codes? Does the car run normally once its hot?

I recently changed the crank position sensor, ran a bottle of injector cleaner, deleted the pcv system (and es plugged the hole to the intake manifold and dipstick tube), and replaced the vanos seals last saturday.

However there is a hissing sound coming from somewhere under the manifold which I thought was normal because I couldn't find any leaks (using starter fluid). so maybe I have a vaccum leak. How do you smoke test without a smokemachine?

and yes the car runs normal again as the engine warms up! after 1 minute of driving it runs normal again.

[Beer+Oversteer]

I recently changed the crank position sensor, ran a bottle of injector cleaner, deleted the pcv system (and es plugged the hole to the intake manifold and dipstick tube), and replaced the vanos seals last saturday.

However there is a hissing sound coming from somewhere under the manifold which I thought was normal because I couldn't find any leaks (using starter fluid). so maybe I have a vaccum leak. How do you smoke test without a smokemachine?

and yes the car runs normal again as the engine warms up! after 1 minute of driving it runs normal again.

What kind of intake manifold are you running? OBDII manifolds are notorious for having the idle control valve fall out of the grommet connected to the intake and cause vaccum leaks. It's a real pain. I would be leaning towards vacuum leak if you're hearing a hissing noise from the manifold.

[Denjeesi]

What kind of intake manifold are you running? OBDII manifolds are notorious for having the idle control valve fall out of the grommet connected to the intake and cause vaccum leaks. It's a real pain. I would be leaning towards vacuum leak if you're hearing a hissing noise from the manifold.

I have an M52 obd1 car. where does the idle control valve sit exactly, can't spot it.

[Eric93se]

I recently made a smoke machine, look on YouTube. Glass peanut butter jar, old soldering iron, cotton sock, mineral oil (rubbing oil). An air compressor is best but a foot pump will also work, slow air flow.

Idle valve is on the right side of the manifold, 2/3 the way back. Not easy to get to it unless throttle body is removed.

[Denjeesi]

Ok I'll look it up, do you have a link?

Strange, today the car idled fine at cold start although it was even colder then yesterday. I will still check for vacuum leaks because of the hissing, and replace the MAF.

[E36328Coupe]

Don't under estimate the impacts of cold and damp in winter on old insulation. When you hear hooves think horse not zebra. Also do some diags.

[Denjeesi]

Don't under estimate the impacts of cold and damp in winter on old insulation. When you hear hooves think horse not zebra. Also do some diags.

What do you mean by old insulation, referring to what exactly? I have an obd1 car, I can't read codes, and I don't have a check engine light because it is a European model so I can't even do the "pedal trick" to read the codes..

[E36328Coupe]

Missfires are often breaking down coil pack insulation in damp conditions.


OBD1 do do diags, trick is what ECU? And then getting the stuff to read them.

ECU and year would help

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Think of it like this. Car was fine, what changed? Weather. Cold weather and a day not running brings damp air and condensation - just like the outbreak of ill informed "has my head gasket gone" threads every winter.

[Denjeesi]

Missfires are often breaking down coil pack insulation in damp conditions.


OBD1 do do diags, trick is what ECU? And then getting the stuff to read them.

ECU and year would help

- - - Updated - - -

Think of it like this. Car was fine, what changed? Weather. Cold weather and a day not running brings damp air and condensation - just like the outbreak of ill informed "has my head gasket gone" threads every winter.

So you say that its "normal"? I have another set of coilpacks, I could install them instead of the once I curently have installed

I have an MS41.0 ECU, but my m52 engine was one of the first to leave the factory, for these they used a different ECU without eprom chip for the first few months.

[E36328Coupe]

Didn't say normal. Said look for what changed and that it does happen. Not that it has happened to you. Test by substitution is valid IF the other set are known good

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So you say that its "normal"? I have another set of coilpacks, I could install them instead of the once I curently have installed

I have an MS41.0 ECU, but my m52 engine was one of the first to leave the factory, for these they used a different ECU without eprom chip for the first few months.

I have the earlier 328 non-flash MS41, reads fine in INPA

[marvinstockman]

Until you solve your problem, use the gas pedal to keep the revs up (say 1000 to 1200) until the engine smooths out, say for 30 secs.

[Eric93se]

Yeah I wanted to suggest INPA but not aware of what early year E36's supported it. I guess if you have the round port under the hood, you should give INPA a try.

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You deleted the whole PCV system, what did you put on the valve cover port?

[Denjeesi]

Yeah I wanted to suggest INPA but not aware of what early year E36's supported it. I guess if you have the round port under the hood, you should give INPA a try.

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You deleted the whole PCV system, what did you put on the valve cover port?

Okay I will give the software a try. Do I need a obd1 to obd2 adapter in order to plug it into the laptop?

For the pcv delete I used a rubber plug and for the dipstickhose I cut of the part from the valve that connects to it, then filled it with silicone, let it dry, and put it back into the hose.

[E36328Coupe]

Okay I will give the software a try. Do I need a obd1 to obd2 adapter in order to plug it into the laptop?

For the pcv delete I used a rubber plug and for the dipstickhose I cut of the part from the valve that connects to it, then filled it with silicone, let it dry, and put it back into the hose.

OBDII defines protocols, socket shape etc.
Don't get tied up on these terms. No euro E36 had a 16 pin from the factory SO they are not OBDII even if you use the 16 pin to 20 pin adapter.

INPA Plus an unmodified Vag Com / KKL / ODBII cable + 16 pin to 20 PIN adapter is the starting place for most on the E36 diags with INPA.
The adapters are circa £3-£4
An FTDI FT232RL chipset based Vag Com / KKL / ODBII for about £3-£4 from china is usually the norm.

I can read the same early MS41 on my 328 with the above.

However, I generally choose to use a serial interface and an "Alfmost free ADS" module as it takes care of more modules in the car. See post 508 on the "Almost free ADS" thread on here.


A proper laptop serial post is required for an ADS, few folk have them so usually means an old desktop or laptop

[E36328Coupe]

Search joylove useronbimmerforums.co.uk he has a really good thread explaining the divorce between hardware ad INPA