E46 316Ti Engine Issue

[natch97]

Hi guys.

Don't know if any of you lot read my thread in the welcome section but basically I have just become the very proud owner of a 2002 316ti.

went to get the car on sunday. 2002 115000miles. £1700. bargin I thought.

I asked the guy why it was so cheap. He pointed out that it had had a new tailgate because someone had dented it in a car park and that sometime in it's life it had a blow over that was not the best job. I checked over the body work. All the panels lined up and there was no other sign of damage.

Test drive was fine. Full service history but in need of a service last 1 was 12000ago.

So to my problem. THe car loses power at exactly 1500 rpm to 2000rpm when it is warm. There is no problem when it is cold. It feels like 1 big misfire. It is the same in any gear but most noticed in 3rd and 4th. I seems ok once you are over 2000 rpm but sometimes does feel nippier then others.

If I turn the car off and go back in 5 mins the temp gauge will not have moved but the problem will go until I get to the end of the road and then come back.

I have changed the spark plugs with NGK platiniums, changed the air filter, oil filter and oil for castrol edge 5w-40w but the problem is still the same.

Any ideas on this would be great. If I can't fix it myself then I will have to take it to a garage but I prefer to have an idea first. :(

[Guest Mister Dabsy]

Personally I would get hold of a friend that has a laptop and OBD cable/software and get some fault codes...

I would suspect that it is electrical and could be the Throttle Sensor but It's difficult without being there :mellow:

[natch97]

Cheers. Does anyone in the bristol area have one of these cables/software.

If not can someone tell me the best place to get it from and price.

[natch97]

Got it booked in at a local bmw specialist. I've done all the simple stuff that i can e.g. checked coils, changed spark plug, oil, fuel filter and cleaned the MAF sensor. Just fingers crossed it's something cheap.

[G4VHD]

Lets us know how you get on mate

[natch97]

Will do

[natch97]

AHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHh!!!!!!!!!!!!!!

I took my bimmer to a " specialist". He hooked it up to the diagnostics, found no fault codes. Took it round the block, bunged in some injector cleaner, shrugged his shoulders and said it was ok. 60 quid... Cu$£.

On the up side I went straight to the guy who does my MOT usually. He said bring it in next week and he will find the problem if it kills him and will only charge me a maximum £35 for 1 hr to find the fault and then what ever to fix it. He is a good guy but not a specialist. Langdon Motors Totterdown Bristol.

[andy-mcq]

So you paid 60 pound to some one who hasn't fixed it and did pretty much nothing!

[Luke]

So you paid 60 pound to some one who hasn't fixed it and did pretty much nothing!

Haha I lolled at that andy you legend!

[Guest Mister Dabsy]

I wouldn't have gave him full whack for there zero result !!!

[natch97]

Unfortunately he did state the price of the diagnoatic before I booked it in so I didn't have a chose.

I thought of just getting the spare key and driving off but I did a case study in law where a guy took his car from a mechanic without paying and got done for theft.

[Guest Mister Dabsy]

Sods law mate... They charged you for time and not result... Tw4ts !!

[natch97]

Yeah! Well you live and learn

[gogoman]

Hi,

New on here myself, just reading about your problem. I am a fully qualified mechanic and reading what you have put, it sounds maybe like its 1 of 2 problems....the first being ECU temperature sensor, which is giving false temperature reading to ECU, this can only be found by going into live data on diagnostics machine when vehicle is cold!

The second is failing fuel pump when getting hot, not delivering correct fuel pressure when warmed up! The only way to tell this is to go on manual pressure gauge and run vehicle up to operating temperature!

These are two things that spring to mind and are common in most vehicles, hope this helps...

Justin

[Guest Mister Dabsy]

Just to add Justin... The ecu detects fuel pressure too...

As for "failing"... It either works or it doesn't !!!

Nice input though, mucka ;)

[natch97]

Cheers guys. I will suggest this to the mechanic on tuesday and see what he says.

[Guest Mister Dabsy]

Hi,

New on here myself, just reading about your problem. I am a fully qualified mechanic and reading what you have put, it sounds maybe like its 1 of 2 problems....the first being ECU temperature sensor, which is giving false temperature reading to ECU, this can only be found by going into live data on diagnostics machine when vehicle is cold!

The second is failing fuel pump when getting hot, not delivering correct fuel pressure when warmed up! The only way to tell this is to go on manual pressure gauge and run vehicle up to operating temperature!

These are two things that spring to mind and are common in most vehicles, hope this helps...

Justin

The temp sensor issue would only fuel the cylinders more...cold = more fuel...

Like I said, a fuel pump will either work or not, its a simple motor with a tank filter....

[Greeney2k1]

have a go at cleaning the air flow sensor that would be my first best guess the cars not regulating air / fuel properly when the engine warms up

[Guest Mister Dabsy]

... And the Throttle body because that can become an issue on any car

[G4VHD]

Dabs beat me to throttle body :P

[natch97]

Ok so up date.

Getting to the point where I will try to sale this car soon. I took it to my usual mechanic. He could find no fault codes. He took it for a test drive and said he thought it could be throttle body. so he took it apart and cleaned the throttle body. It was the end of the day and i needed the car for work. He told me to see how it is and if not better to bring it back.

It is no better. I am loath to take it back as I think he is clutching at straws and guess work.

I've got a friend to look at it. The engine is getting louder as time goes on. Like the tappets, ticking noise. He is going to do a compression test on the cylinders tonight just to rule that out. He thought maybe it is running on three cylinders and the sound is a bit like the old twingos. I'm not sure but we will see.

The bit that i don't get is that all the problems people have suggested to me would be like that from cold. Why would it matter when it gets hot. also things like MAF and sensor faults would A. usually throw a code and B. don't explain the ticking noise.

Lastly When I took it to the mechanic he said they did a "valve test" and the noise whent away and when they finished the test it came back. Does anyone know what he was talking about and could this lead to an answer.

Please Please help me with any ideas as I love this car but cannont afford to drive it 80 miles a day as it is costing me the best part of £20 at the moment on the motorway. :(

[Guest Mister Dabsy]

From your explanation it could be oil pressure. Lack of it will "Rattle" the top end and maybe overheat, resulting in the cyl head warping a fraction, this in turn, lets the gasket give way.

Do you get warning lights whilst engine is running?

When was last service?

Just another angle for you to consider pal...

DAZ

[Luke]

Try the air flow meter first mate they are so common to 'break' not 'fail' right dabsy ;)

[Guest Mister Dabsy]

Try the air flow meter first mate they are so common to 'break' not 'fail' right dabsy ;)

Very true Luke, they get clogged just like the throttle body and still give good signals to ECU, But really shouldn't make the motor run like a Citroen CV2 on one pot !!!