car wont run properly m20 2.5

[matt86]

My car has done a similar thing for the second time in 4 weeks. It won't go above 2000 revs and is like its being choked, last time it was air leaks, the idle is erratic too, I don't know whether to just change all the air hoses. Any thoughts. Cheers

[Quaser]

could be dizzy cap/rotor maybe??

[Rtaylor2208]

What did you change the last time?

[matt86]

Its had new dizzy cap and rotor. Do you think it could be a fuel issue or plugs?

[matt86]

Its had new dizzy cap and rotor. Do you think it could be a fuel issue or plugs?

[matt86]

Also it keeps stalling, I need help with it asap, as it hasn't broke down in a ideal place and going to a show Sunday.

[Rich320I]

what have you checked to date matt? theres not much point in changing everything without locating the problem really.

AFM, ICV, has the fuel filter been changed etc etc. theres a few tings that could be causing the issue. is this on the 2.5 fitted in the cab?

[Mo13]

I'm guessing you changed the AFM boot....I would test/rule out AFM & ICV first

[Rtaylor2208]

Matt you need to be methodicial with this kind of problem.

So here goes.

To rule out air leaks you need to check the following:
1. All vacum pipes, some are not particulary easy checked without disconnecting them, for example the breather pipe between the throttle body and the rocker cover.

2. Are all connections from the vacum pipes tight and secured with the correct jubilee clips where required. Such as the the rubber boot between the AFM and TB, between the ICV and TB, between the brake servo and TB?

3. When was the last time any of the seals \ gaskets on the inlet side were last inspected or changed? The common ones are inlet manifold gaskets between the block and manifold, throttle body gasket between the TB and inlet manifold. The Oil filler cap, the dipstick o-rings, the rubber bung on the underside of the throttle body, the o-rings used to seal the oil pickup tube between the block and inlet manifold. The rocker cover gasket.

Then you are looking at testing the ignition related components such as:

1. Blue temp sensor at both the sensor itself and the ECU (see wiki)
2. The resistance of the TPS at differently throttle settings (see wiki)
3. Testing the AFM, requires a 9 volt power supply (see wiki)
4. Testing the injectors are clicking when active, possibly have them refurbished by injectortune if its not know the last time they were done. (see wiki)

[Rtaylor2208]

Its had new dizzy cap and rotor. Do you think it could be a fuel issue or plugs?

This would also not fix air leaks, what did you do the last time on the airleak side of things?

[Rich320I]

think thats the same question been asked by 3 different people.

[matt86]

Tightened the jubilee clips up onbtubing and seemed to run better. Im wondering if its a air leak again. Any other ideas?

[matt86]

Tightened the jubilee clips up onbtubing and seemed to run better. Im wondering if its a air leak again. Any other ideas?

[Speedtouch]

Which ECU do you have? The 0 261 200 380 type is reknowned for blowing diodes in the idle control circuit.

Also, is the engine-to-body earth strap in good condition and properly bolted down?

[BenHar]

Get some carb cleaner, WD40 or lighter gas and spray it round the inlet manifold, throttle body and MAF with the engine running. If the engine speed changes you have an air leak.

Ben

[pukar]

i had the same problem, it was the ECU

[matt86]

Idle is sweet now after changing idle control valve. Air flow sensor and air flow tybing from my other e30, but when accelerated anything over gradual acceleration, it jumps and won't go, but fine if you accelerate slowly. Also when vehicle is stationary will rev up to the red line, im thinking fuel/air issue when under load, possible blocked fuel filter? Cheera

[oomz1975]

I had this issue a couple of weeks ago, turned out to be the rubber boot between the trottle body & afm wasn't secured correctly.
Re-fitted it properly & since then it's running sweet again.

[jonny323i]

What else have you got that you can swop over to check for changes in symptoms

[jonny323i]

What else have you got that you can swop over to check for changes in symptoms

[Speedtouch]

Idle is sweet now after changing idle control valve. Air flow sensor and air flow tybing from my other e30, but when accelerated anything over gradual acceleration, it jumps and won't go, but fine if you accelerate slowly. Also when vehicle is stationary will rev up to the red line, im thinking fuel/air issue when under load, possible blocked fuel filter? Cheera

It could well be that, or a perished rubber fuel hose. I had a Fiat twin cam with a similar problem - severe flat spots and kangarooing under certain load conditions, and when I removed the aftermarket inline fuel filter, the problem disappeared.

[matt86]

What else have you got that you can swop over to check for changes in symptoms

The whole lot John, I have another M20 but the 2 litre engine, was going to try ht leads, coil (ignition system bits next), then a fuel filter, have already put all the air hoses from one to the other.

I think some redex, a fuel ilter and clean the injectors might be the way forward.

Any other advice very welcome.

Cheers

Matt

[jonny323i]

Iv got loads of known working 325i stuff like afm etc etc if you wanna try anything if you can make it to stoke

[matt86]

Iv got loads of known working 325i stuff like afm etc etc if you wanna try anything if you can make it to stoke

thanks john, I cant make it up there anytime soon unfortunately.

I've got all the bits from the other e30, but as we all know that doesn't mean they will work either, I was seriously debating whether to buy it all new from bmw, all the ignition system, air hoses, temp sensor etc, to rule everything out and so it runs nice, it will obviously cost a lot to do though.

[jonny323i]

Your not kidding you would need a mortgage is get the pipes from BMW that rocker pipe is a common one the temp sensor eco do for a quater of the price.
If you can get up Iv got :
Afm
Afm boot
Temp sens
Icv
Ecu
New Bosch plugs
Dizzy cap
Leads

[matt86]

Your not kidding you would need a mortgage is get the pipes from BMW that rocker pipe is a common one the temp sensor eco do for a quater of the price.
If you can get up Iv got :
Afm
Afm boot
Temp sens
Icv
Ecu
New Bosch plugs
Dizzy cap
Leads

thanks john will beqr it in mind, I think its a fuel issue, will try fuel filter firdt

[matt86]

is that the best thing to do next fuel filter and redex, to clean the system throygh?