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Gus

Cold Running Problem

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when cold, my car runs like a bag of arseholes. runs on about 4 cylinders, misfires esp around 2k rpm.

is much better when warm, but still feels like a misfire just above idle, which makes moving away from stationary a pain in the ass.

have replaced the water temp sensor with a good one, not much more diagnostics yet, gonna work through the bentley manual. looking for ideas though! suspiciously close in time to the steam clean it had last week.

any ideas appreciated, sick n tired of looking like a complete n00b in traffic!

my cam probably doesnt help, but is def something underlying

also, after the steam clean, head rebuild and a bit of thrashing, lumpy idle is gone..idles lower (around 600rpm) and sounds like a normal car!

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Guess at water in electrics somewhere, getting warm and running sweet but then condensating as it cools?

If not just throw $$$ at it usually works..

cheers Matt

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welcome to my world! i just kiss my lucky egg so i don't break down.

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it was a bit of a stretch to reach my lucky eggs so i came up with the following

seems to be moisture in the AFM...replaced with a spare i had and did it even worse..cleaned the current one with carb cleaner and opened the top and got as much out as i could..need to get it nice n hot to dry it off. waiting for it to cool down so i can test again!

wouldnt be surprised as the cap was loose, and it did get a healthy spray of water/steam.

fun

also replaced with BMW coolant as instructed by will, and front pads. non OEM ones suck! toasted after half a puke day and a taupo driver training. and the appropriate road use :)

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Just buy your old one back, it idles just fine when it's cold! :rolleyes:

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mine does the same check plugs and leads check air fuel mixture. also try and work out if your computer is giving you enough gas at cold idle. where abouts are you located? if your in wellington area pm me and i will try and help.

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am in auckland

some early morning sunday investigation may have resulted in something

dizzy rotor has around 1k resistance between the centre and arm..should be zero!

also finding it hard to get a reading from dizzy cap points to the end of the plug lead...too much resistance..plugs are carbon fouled hard..so i imagine is the inside of my nice clean head :(

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well thats never a good thing a did you check the resistance of your ht leads aswel? should be around 50k ohms for every 30cm

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more around 5-6k...not 50! haha. my # 1 lead has virtually no continuity, gonna change that, the plugs and the dizzy rotor and see how i go

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well thats never a good thing a did you check the resistance of your ht leads aswel? should be around 50k ohms for every 30cm

E30 leads are copper, the plug cap and dizzy cap are the supression bits, so length of lead has no effect on resistance. The complete plug leads should measure no more than 6K if my memory serves me correctly. The HT lead from coil to dizzy reads a lot lower than that, (again caps provide the suppression, lead is copper) can't remember exact maximum though.

Will

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replaced my #1 lead with a new one...didnt replace rotor as the new one had the same resistance. new plugs and....fouled after 30seconds running. disconnected coil lead produces a healthy spark...there must just be fuel constantly going through the engine.

this is so FTL, hope i can make taupo!

will, might have to take apart and fix that plug you were talking about..re solder. hmm fun. could make sense why injectors are opening all the time (if thats the case)

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may have a lead

the injector loom under the manifold, most of the connectors seem to have continuity of some sort between each one..surely not a good thing! so they are not acting as individual injectors but one..that sound right will? out comes the soldering iron/hammer

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also...should not the AFM's resistance increase constantly...mine rises then drops down before rising unsteadily

sound about right (well wrong, but may have found my problem)

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may have a lead

the injector loom under the manifold, most of the connectors seem to have continuity of some sort between each one..surely not a good thing! so they are not acting as individual injectors but one..that sound right will? out comes the soldering iron/hammer

motronic 1.1 fires the injectors in 3's prob the same in 1.3. so 1,2,3 and 4,5,6 fire together.

I would think the afm would rise steadily not jerky like you describe. Will attempt to measure one here and see if I get a dip.

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ok, found one out of motronic 1.3 but get much the same as you do, get a sharp dip not long after opening it.

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undid all injector wires from plug..re did them.

borrowing an afm that works...now she doesnt start

must have done spark plug wires wrong.

nice healthy spark too..must be an fueling/electronic prob

gayness!

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lose! maybe you put in diesel instead of petrol?

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well..a borrowed AFM helps...(one injector plug had pushed itself out...n00b) and it seems better but its kinda hard to tell as its running on 3 cylinders...

if i unplug 2 4 or 6 makes no difference to running of the car...im sure those 3 are connected somehow...ah wel..back to it!

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well sorted that...had an injector wire coloured wrong so i wired up wrong..my bad

got it running..most of the plugs have cleared up a bit but the #5 one is still fouled, and it sounds like its missing on a cylinder so im guessing its that one.

AFM swap has helped heaps, thanks jock. so need to find myself a working AFM! anyone got one?

still got that misfire problem..keeps shooting wee flames out the back and big vibrations when running

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check the electrode gap on the #5 spark plug, worth a try, use feeler gauge, should be 0.8 mm

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yep...and its fine

i hate e30s so much

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Remove the outer shield (black) from y'r distributor cap and make sure it isnt cross firing or shorting to the shield earths (brass inserts in the dist. cap that the bolts go through). You normally see signs of tracking under these shields if you have spark plug or suppressor cap problems. Not many check these when carrying out a service.

Cant help with an AFM tho. What is actually wrong with it...is it sticking??... as in not a smooth action

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no tracking on dizzy cap..has been off a lotta times recently too!

the afm isnt sticking, not sure what is but almost seems to be sending the wrong fuel signals to the ecu and injectors...the test one works fine..still unsure about misfire though

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Have you rechecked valve clearances after running the engine ???...I think I read you put a reco head on this car. After running and allowing the car to get to operating temperature, always allow the engine to cool...overnight preferably and redo y'r valve clearances. They will alter after initial set up.

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yeah i rebuilt the head...didnt realise valve clearances changed after initial setup..car was running fine for a good week or two after doing the head without touching the valve clearances again so i would imagine they are ok?

taking it to mechanic tomorrow if i cant fix it before then!

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