not too interested about fuel economy etc, but will other ecu's (uncoded obviously) for example 899 cinq ecu's get the car to start / run?
Technical mpi ecu alternatives? cinq 899 ecu?
- Thread starter ronnieronson
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Technical mpi ecu alternatives? cinq 899 ecu?
Eh?
What have you done/what are you trying to do? Which car?
What have you done/what are you trying to do? Which car?
OP
OP
still investigating this rough idle on the b***h (mpi sei for those who don't know) - it's 95% sorted, but not perfect.
Ming has a couple of 899 uncoded ecu's for sale - thought it'd be a cheaper start than hunting down a mpi ecu that's uncoded....
I don't think an 889 ECU would give enough fuel to do anything usefull (and the pinout could wll be wrong).
See if you can get hold of an MPI ECU with a key. Untested, this, but should work.
Swap the ECUs over, hang the new key near the inductor, and you should be able to start using your old key.
If it cures it, try and get Timsons to make you a key with the new key's code, cut to the old pattern.
But lumpy idle could be little more than a valve issue. Compression test? Check the clearances.
See if you can get hold of an MPI ECU with a key. Untested, this, but should work.
Swap the ECUs over, hang the new key near the inductor, and you should be able to start using your old key.
If it cures it, try and get Timsons to make you a key with the new key's code, cut to the old pattern.
But lumpy idle could be little more than a valve issue. Compression test? Check the clearances.
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I have an mpi ecu ... what version do you have? 4af? one or two plugs?
Kristian
Kristian
an 899cc cinq ECU won't even fit nevermind run the engine..
Jesus christ not again!
i bet you havent done the compression test yet have you? Is there any reason why you are avoiding doing this?
i bet you havent done the compression test yet have you? Is there any reason why you are avoiding doing this?
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OP
OP
Done the compression test - will come back to that in a mo...
2 plugs - small type - can't find any serial numbers on it though
Fair enough
As above the results are in - forgot where I put the bit of paper with my results on, but having tidied the study (workshop
) up this morning, I've found em.Dunno which cylinder is supposed to be which, but working from the left (drivers side) of the engine the readings are as follows:
* 15bar (220 psi -ish)
** 14bar (210 psi -ish)
*** 14.5bar (215 psi -ish)
**** 15bar (220 psi -ish)
Worth noting that the fourth one (right side) was quite oily...
Can't really conclude a lot from those figures. Don't seem far out. No.4 may have a knackered valve guide which a blow down test might show up. Worthwhile checking the valve clearances, though: chances are it has never been done since the engine left Poland!
wouldnt expect no4 to be oily, only no1 as its near the oil cap. unless its just seeping down the from a leaky cam cover gasket.
BUT i would class a variance of 1bar between two cylinders (ie what you have) as indicitive of a problem.
BUT i would class a variance of 1bar between two cylinders (ie what you have) as indicitive of a problem.
I'd not expect it to be oily 'cos that cylinder runs a bit hotter. But are we talking oily outside, or oily on the inside? And where inside?
It's, what, 7.5% or so? (Can't do the maths, have touch of arc eye, need sleep.) Anything more than 5% spells trouble on a competition engine, but on a road car with who knows what mileage? More significant may be that 2 adjoining cylinders show lower figures.
OP
OP
blow down test?
oily on the threads... dry on the sparky end
35k is the current mileage - head gasket was done (inc skim, and a truck load of other work cambelt etc) at 26k(ish)
Got me thinking that the head may be banana shaped?
Would this explain the hunty idle?
General running of the car seems fine - pulls nice and hard, and will (on a private track of course) hit 105 (on gps - 115ish on speedo).
Only things I can think of (or have had suggested) are a dicky TB, bad ecu (which I know there was an iffy batch - but I dunno what's the serial number or how I'm supposed to tell etc) or a warped head.
not warped head, HG blown between two cylinders maybe.
oil on threads but not on the plug ends mean its nothing to with oil in the cylinders, therefore irrelvant.
oil on threads but not on the plug ends mean its nothing to with oil in the cylinders, therefore irrelvant.
OP
OP
Right - not convinced this has anything to do with my slightly hunting idle, but I am convinced it has everything to do with my low idle - read on:
Had a poke around near the accelerator pedal today (was rearranging sub cabling for my new boot install - see other post later on today), and noticed that the rubber grommet thing on the throttle cable at the pedal end, seems to have corroded/broke.
It seems logical that if my pedal is not taught and at the right height (which it isn't - it seems way too high, but I always assumed it was normal), then my rpm at idle would be a little low?
If this is the case, what is the simplest fix? tighten the torx nut at the butterfly? or is this a new cable job?
Had a poke around near the accelerator pedal today (was rearranging sub cabling for my new boot install - see other post later on today
), and noticed that the rubber grommet thing on the throttle cable at the pedal end, seems to have corroded/broke.It seems logical that if my pedal is not taught and at the right height (which it isn't - it seems way too high, but I always assumed it was normal), then my rpm at idle would be a little low?
If this is the case, what is the simplest fix? tighten the torx nut at the butterfly? or is this a new cable job?
has nothing to do with it. you could cut the accelerator cable and the car should idle perfectly. it has handled by the idle control valve, not the throttle butterfly.
No. The cable should have some slack in it: I recon that the rubber being knackered will just increase the slack.
Idle is controlled by the throttle position sensor and ECU.
"Correct" thing to do is buy a new cable anyway.
How low is the idle?
Idle is controlled by the throttle position sensor and ECU.
"Correct" thing to do is buy a new cable anyway.
How low is the idle?
Ronnie, I think you're trying to fix a car that's working perfectly.
Thing is with the MPIs is they are meant to idle very low, both my MPIs on the stock ECU idled at a rather lumpy 680 to 700 rpm. In fact my 2nd MPI failed on emissions the first time round because I'd got it to idle smoothly, this put the rpm above the 850 rpm limit, after getting the idle to 830ish rpm it was back to a lumpy idle again.
Thing is with the MPIs is they are meant to idle very low, both my MPIs on the stock ECU idled at a rather lumpy 680 to 700 rpm. In fact my 2nd MPI failed on emissions the first time round because I'd got it to idle smoothly, this put the rpm above the 850 rpm limit, after getting the idle to 830ish rpm it was back to a lumpy idle again.
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record the car idling, let's have a listen.
i said that months ago, thank god im not the only one with the same thinking
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OP
OP
Is the ICV the same thing as TPS?
I know everyone keeps saying it's working fine (including the garage) - but it idles at between 500 and 800 rpm, depending on what mood she's in.
It's not actually the low idle that's the problem - it hunts still, despite all the work done...
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