Engine Rattle

[jackherer 543]

http://web.archive.org/web/20150329103701/http://the944.com/afm.htm

 

Sadly it looks like Mr F R Wilk hasn't paid his hosting bill...

[scbond 15 1 Cars]

Starter isn't the cause, though worth sorting before it dies fully.

 

I'd still say it's something along the fuel system and possibly damage caused by the water. Have you checked the injectors as Tom suggested.

 

As for the mileage and whether the car is past it or not...a car is only ever past it once the owner gives up on it. Mileage is just a number and faults, however extreme, can be fixed. Hang in there and you'll get to the bottom of it!

[Telf 222 2 Cars]

This afternoon a borrowed another AFM off Jackherer. Started up and it died pretty much straight away. Gave it another go and this time it kept running. Left it to idle for 1/2 an hour. So an improvement as it didn't stall or backfire.

Took it for a drive. Good power - running ok. Had a couple of minor stutters but no massive choke and loss of power.

Ah ha! Thinks I - getting somewhere now. Parked up. Stopped the engine and restarted- no issues.

Had a chat with Jackherer about the hesitation and decided to change the ECU and tacho relay back to the original units. Set off again. INSTANT hesitation - what gives ?!? Surely I don't have a unserviceable ECU and AFM

[Telf 222 2 Cars]

And another back box goes bang- was running nice right up to the moment it went bang...

[Tom Fenton 1,525]

I would have the injectors cleaned/tested. If one is leaking fuel constantly no amount of different ecu or afm can help. Would also explain rich fuel smell, stutter/misfire, and fuel building up in the back box then exploding it.

[Jon_Bmw 13]

I had a very similar problem on a 16v many, many moons ago. Symptoms were pretty similar, it would run until it got warm, then, miss, miss, die.

Turns out there was a very small burn mark on the rotor arm, that was only visible from the camshaft end. We guessed that for whatever reason, it warmed up, then arced to the camshaft rather than the dissy cap. Anyhow, a new rotor arm fixed that, whether it does yours I don't know!

 

Its easy to check and cheap to swap, so worth checking before you tear all your hair out?

[Telf 222 2 Cars]

Hi Jon,

 

The rotor arm is new - about 3 months old so I don't think its that

[Telf 222 2 Cars]

Tom,

 

I don't think its an individual injector, heres a picture of all 4 sparks- bearing in mind I recently changed them they are all (I think) showing equal sooting up so I think its a problem across all 4 cylinders. What do you think?

They are all showing a burn mark on the back too-

[Telf 222 2 Cars]

Could a faulty fuel regulator be causing an overfuel issue?

 

I will take the injectors out if needs be - I'm going to check the wiring from the tacho and ECU to the injectors when it stops raining

[Simes 248 2 Cars]

Is it charging ok?

[Telf 222 2 Cars]

Hey Simes,

 

Yes it fine- again alternator was replaced in March - Lucas recon unit working ok

[scbond 15 1 Cars]

Re the fuel pressure regulator, not sure it would cause this much of an issue. You can test it using Mei's method...just search for fuel pressure regulator testing and you'll see it.

[Telf 222 2 Cars]

OK will have alook

 

Thanks

[Telf 222 2 Cars]

Think I may have found the fault....

 

Wires from the dizzy- see picture

 

Which leads to the age old - never overlook the basics..

[Telf 222 2 Cars]

Well that didn't work!

 

Just as bad as before so I have taken off the throttle body and inlet manifold to see what clues there are- also to look at the injector loom!

 

All 4 ports on the Inlet are pretty Sooty. The Throttle body has a Rim of black sludge around the collar

[Telf 222 2 Cars]

Here a couple of pics of the valve inlets

Some filth around the rim but it seems clear inside - I'm not sure what this means really.

 

I'm planning on removing the injectors and sending them to be cleaned/checked - I seem to remember someone on the forum offers a injector service - cant find it though, does anybody know please?

 

Any thoughts on the pictures etc more than welcome!

 

[Jon_Bmw 13]

Hi Jon,

 

The rotor arm is new - about 3 months old so I don't think its that

Worth checking for the time it takes, assuming your problems started after the new one was installed.

 

If not given the condition of that wiring, I wonder if there is anymore like that elsewhere?

[scbond 15 1 Cars]

Have you checked the rest of the wiring loom in the engine bay for similar issues? Not sure how likely it would be but could possibly have resulted from water damage (water sitting, causing a short etc) though unusual for it to happen mid-wire unless something else was at play, like a break in the wires were the damaged has occured.

[Telf 222 2 Cars]

Hey,

 

Today I've had all the looms stripped and cleaned - no damage any where, the engine bay has been completely cleaned and degreased. Each wire to all the ignition/fuel components has been checked for splits/damage. The pins to each plug - AFM, coolant sensor, injectors, Coil, Starter, alternator all checked - no issues. Checked the earths -no issues. Plug to SAD checked, in fact every wire in the bay checked. At a loss now!

[steve@cornwall 100]

How much fuel was in the oil? From the inlets it looks like the breather system has been feeding oil to the inlet. May be interesting to see if the inlet is full of waste oil too. Have you changed the oil? Could be you're suffering the after effects of the old coolant sensor dumping too much fuel past the rings.

Edited October 18, 2015 by steve@cornwall

[Telf 222 2 Cars]

Hi steve,

 

Inlet had a bit of oil in it- I think this is fairly normal isn't it?

 

I've wondered if the oil is contaminated to the extent that its basically producing a vapour bomb of the whole system.

 

All the oil breather pipes are off and cleaned -no splits any where.

 

Unfortunately the coolant sensor wasn't at fault - tested against the replacement they read similar resistances at a given temp.

 

I tested the fuel regulator today - it opens at 3.5 Bar so that's not faulty either.

 

Still at a loss, seriously looking at buying all new components - well Amplifier,Coolant sensor ,AFM(if I can get one) ECU and just replacing the lot.

 

I don't know if a faulty distributor could cause this kind of fault - I replaced the wiring but not the Dizzy.

 

I also checked the pri/secondary windings of the coil - 0 and 8K Ohms so all good.

 

I'm going to fully removed the Engine loom and visually check the rest of it - probably put a MEGA on it looking for resistance breakdown as well.

 

The only bonus I can think of is as I've hit another brick wall is I have been cleaning the engine bay and block - Its quite therapeutic brushing on Gunk and cleaning it back to shininess. Additionally I've found an old mini screwdriver and a few bolts that have been dropped over the years.

 

Anybody else got any ideas please?

[jackherer 543]

The fuel reg should be 3.0 bar, what are you using to test it?

[Telf 222 2 Cars]

It started opening at 3 bar - was fully open ( ie squeaking noise loudest at 3.5 ). I'm using a compressor to test it mate

[Telf 222 2 Cars]

Today I've tested my original AFM against 2 others - readings are all within a few Ohms of each other.

 

Also checked the original temp sensor against another at different temps - again all good

 

Double checked the throttle switch and set up on the throttle body -readings ok

 

Checked the resistances of the injectors coils - 0 Ohms as I expected

 

Is it possible for the Cam belt to have slipped - would that cause an issue - I mean I imagine it would cause a whole load of other problems but idle and acceleration ( when it runs ) are as I expect

[steve@cornwall 100]

Usually on tooth out either way can run "ok" (just low on power) 2 teeth out and its noticeably rough from start up.