Tuning specialists SE?

[Morf]

Can anyone recommend a decent garage or engine specialist in the South East? I have a running problem on my 325i and none of the garages I have taken it to can identify the problem.

[hongkongfuey]

Where are you?

[Morf]

I am in Rochester, Kent.

[Brianmoooore]

I have a running problem on my 325i and none of the garages I have taken it to can identify the problem.

Tried asking on here? There's far more collective knowledge about E30s on here than in any garage.

[Speedtouch]

What are the specific problem(s)?

[Morf]

Ok let me try and explain. At low revs it drives fine but as soon as I give it some poke it stutters and the power doesn't come in for a second or two then at higher revs it's fine. I can't tell you the rev range because the rev counter is inop! (next on the list to sort).

I have fitted brand new plugs, leads, dizzy cap and rotor arm and chucked two bottled of redex in the fuel system.

[Speedtouch]

Try disconnecting either the ECU or battery and leave it for an hour or so to reset the ECU.

Then let it idle for at least 10 minutes to enable base idle settings to be learnt. Then switch off. Then take it for a drive throughout the rev range; this ensures full data transfer from the EPROM chip to the processor.

[Morf]

Ok I will try that later. I forgot to mention I also fitted a new Air Flow meter on it yesterday and when i finished fitting it I forgot to replace the plug and it ran badly but still drove. When I realized I left the plug off I refitted it and took it for another drive and it made no diffference at all.

[Speedtouch]

Try testing the AFM using a multimeter. It is a simple rheostat (variable resistor) that varies depending on the flap angle; it should vary linearly.

http://www.r3vlimited.com/board/showthread.php?t=247831

[Morf]

This is where the problems start. I don't have a multimeter and I am not completely sure what "linearly" means. I'll try and borrow one and read up on that link.

[Speedtouch]

Linearly means the resistance value varies in a smooth and progressive way. If the carbon track is worn, it will jump or drop out (infinite resistance), which throws the ECU into confusion.

[Morf]

You seem to know what is what and you are local. Do you have a garage perchance?

[Speedtouch]

I am just used to working on my own cars, having owned four E30s.

[Brianmoooore]

You won't get a reliable test of an AFM using just an ohmmeter to measure the resistance to the slider as the flap opens. You need to connect a 6 or 9 volt battery (PP3, PP9, etc.) across the ends of the track, and measure the voltage on the slider pin as the flap is opened.
The voltage change with flap angle is not linear, but MUST always increase - never at any point dropping back, even slightly. If it does, positive feedback will occur, and the ECU fuel control is likely to start a low frequency oscillation, giving considerable driving problems.
The chances are that most 'mechanics' you take your car to in an ordinary garage have either no idea what an AFM is or how it works, or it has been so long since they saw one, they have forgotten.
You can buy a meter for as little as £5 or so, but I recommend you go mad and spend twice that!
The symptoms you describe are typical of an E30 in need of a FULL service after many years of neglect.
A set of reconditioned injectors, a thorough hunt for and elimination of inlet side air leaks, and a check of the operation and calibration of the throttle position switch, and I suspect you will have a very different car, with bonuses in both the BHP and MPG departments.

[Morf]

Where can I get a set of injectors from? And is there a guide on how to check for air leaks? I did an engine oil and coolant flush/change and replaced, leads, plugs and dizzy cap and rotor when I bought it. It ran nicely for a while but has started this nonsense now. Is there nobody that would like to take on this "service" for some cash money?

[Speedtouch]

PM sent.

[aimlessrock]

sounds like injectors”¦had mine cleared and over hauled and she ran much better”¦

[Brianmoooore]

You either send off the injectors you already have to be rebuilt, or obtain another set, and send them off.
See Injectortune in our traders' section.

[Morf]

Thanks I will try that.

[Morf]

Noob question. How do i remove the injectors? Is there an idiots guide? I have disconnected the battery...

[Speedtouch]

http://www.e30zone.net/e30zonewiki/inde ... _injectors

[Morf]

That guide doesn't mention removing the intake manifold. Is that right?

[Speedtouch]

http://forums.bimmerforums.com/forum/sh ... -1991-325i

[Morf]

I've tested the MAF's (I got a spare from Charring BMW breakers) and they are both giving the same readings so either they are both ok or both borked. I am going to attempt to get the injectors off next.

[Speedtouch]

I would first check the condition of the spark plugs - are they all the same light tan colour that they should be?

If not, run a compression test to ensure all six cylinders are reading around 170-190psi before removing anything.

[Morf]

Unfortunately the plugs are all new and I don't have a compression tester.

[rich318i]

pm'd

[Morf]

Still looking for someone who can come and check this car out. Car is unisured now and garaged so can't be moved.

[Morf]

I emailed about getting the injectors serviced but I cant figure out how to do it so will need to take it to a garage with a set ready to go on. Are these the ones I need?

http://www.ebay.co.uk/itm/BMW-E30-325i- ... 1c4048ac3a