idle control ecu

[Sutty2006]

I’ll post it to you. Do what you gotta do, if you don’t break it, send it back when you’re finished? If you do break it, throw it in the bin. Just cover postage? 
 

my cars running so I haven’t taken it out to mess with it yet. 

[cam.in.head]

ah thankyou. the lip around the edge is brittle and does break when you prise it open but im curious to see what difference the 6 cyl ones have to make  them 6 cyl !   il just buy it off you to play with if you like. send me your paypal or a return adress and il send a cheque back to you . ilpm my adress .thankyou. 

 

i will also put a wanted ad up too to see if any correct ones are available .

Edited November 8, 2023 by cam.in.head

[cam.in.head]

ok so an update to this issue.

found a s/h ecu and bought and fitted it. 

worked perfect for a few cold starts. now this replacement ecu is now faulty as well.

obviously ive double checked all the wiring connections to its multiplugs ,they are all doing/ feeding what and how they should.   tried this ecu on my carlton to confirm its definately faulty and yes it is.

carlton system all working fine with its own ecu. as soon as i plug this other one in the revs go straight up to 3000. same as when fitted to other car. (carlton ecu tried in other car works perfect.)

SO  WHAT THE HELL GOES FAULTY . Its driving me nuts now.  opening the units up shows no obvious issues. no bad or cracked solder joints,no burnt areas,components etc. changing all the electrolytics on the original didnt change anything .so are we talking chip corruption or non electrolytic faults.  the boards are very well made and laquer coated too which diesnt exactly help with testing !

i have pictures of opened up unit .i have sent and enquired at a couple of ecu repair places but they are not willing to offer any advice.( obviously because they want to repair them for me rather than me do it !)

icould put pictures on here but would have to email them to a member who could do that for me please .

many thanks. 

[Dave Stockbridge]

Have you tried ATC Drivetrain in Cannock (https://www.atcdrivetrain.co.uk/)? They have rebuilt the LE Jetronic ECU and AFM for our BMW 528 and Motronic for Porsche 944. They offered a lifetime warranty, and were very helpful over the phone in setting up the BMW AFM for emissions. 

      Hope this helps

[2400man]

7 hours ago, cam.in.head said:

ok so an update to this issue.

found a s/h ecu and bought and fitted it. 

worked perfect for a few cold starts. now this replacement ecu is now faulty as well.

obviously ive double checked all the wiring connections to its multiplugs ,they are all doing/ feeding what and how they should.   tried this ecu on my carlton to confirm its definately faulty and yes it is.

carlton system all working fine with its own ecu. as soon as i plug this other one in the revs go straight up to 3000. same as when fitted to other car. (carlton ecu tried in other car works perfect.)

SO  WHAT THE HELL GOES FAULTY . Its driving me nuts now.  opening the units up shows no obvious issues. no bad or cracked solder joints,no burnt areas,components etc. changing all the electrolytics on the original didnt change anything .so are we talking chip corruption or non electrolytic faults.  the boards are very well made and laquer coated too which diesnt exactly help with testing !

i have pictures of opened up unit .i have sent and enquired at a couple of ecu repair places but they are not willing to offer any advice.( obviously because they want to repair them for me rather than me do it !)

icould put pictures on here but would have to email them to a member who could do that for me please .

many thanks. 

Here's the pics of one of cam.in.head's faulty units. (Sorry but they get turned upside down when I upload them - no idea why, and if I turn them upside down, they stay like that grrrrh!)

Edited December 17, 2023 by 2400man

[cam.in.head]

further update.

plugging either faulty unit into the carlton yesterday showed revs rising to 3000 immediately and then my original sprang back into life and regulated the idle after a few seconds. other faulty unit also sprang back to life after a minute or so . there are definately no bad solder joints visible ,board quality is very good anyway ,electrolytics replaced on my original .

SO       are we looking at something that either goesfaulty when cold, unpowered for a while or after powerhas been flowing for a while ?        this would make slight sense BUT idle sometimes went wrong after a journey anyway so ecu would have been powered up for a while by then anyway.

i will email the company suggested above and see if they can offer any advice but suspect they will want me to send them one.  this will no doubt cost a fortune and they will likely say its working ok ( because they do some of the time )

[®evo03]

One of them issues. 

Would it be another fault, possible wiring, or ECU plug. 

[2400man]

12 hours ago, cam.in.head said:

further update.

plugging either faulty unit into the carlton yesterday showed revs rising to 3000 immediately and then my original sprang back into life and regulated the idle after a few seconds. other faulty unit also sprang back to life after a minute or so . there are definately no bad solder joints visible ,board quality is very good anyway ,electrolytics replaced on my original .

SO       are we looking at something that either goesfaulty when cold, unpowered for a while or after powerhas been flowing for a while ?        this would make slight sense BUT idle sometimes went wrong after a journey anyway so ecu would have been powered up for a while by then anyway.

i will email the company suggested above and see if they can offer any advice but suspect they will want me to send them one.  this will no doubt cost a fortune and they will likely say its working ok ( because they do some of the time )

This one gets weirder and weirder doesn't it! I had a word with my mate this evening and forwarded your photos. We'll see what he thinks.......

[cam.in.head]

as i said. its definately the ecu because the fault moves into the other car when i swap the ecu and car that was faulty is fine with good ecu in it. that eliminates any wiring issues etc.

i spoke to the company above who were unable to offer any advice as to what went wrong inside but (as i suspected) asked me to send mine for them to look at !

ive now messaged a few repair places and this was the only one to actually reply.

if i send them one they will no doubt say it is ok as they said they dont have a test rig for that type and can only examine it. it works most of the time so will come back as " no fault found"

i did buy a used one from a member on here which also turned out to be faulty !

its driving me nuts now. short of swapping every component one by one from board to board which wont work as the fault not being constant means this saga could go on for years !

these ecu repair places have obviously done these before in the past but (obviuosly) wont give away any secrets !

 

 

 

 

Anybody else got one to sell 

0280220017 or 0280220018 

[®evo03]

2 x 45's and a manifold. 

Or

 

[cam.in.head]

hi.   motronic is a different system completely ,but it does contain the idle regulation all in the same ecu .along with ignition control as well .

ive watched that video. a couple of failing caps seems to kill them . i did try changing my caps ( 5 electrolytics) but no difference.   my next step is possibly to replace the entire jetronic loom ,the main ecu and the ignition ecu just incase anything there is killing them initially ? 

however ,once i find the actual failing part in the idle ecu al should be we.. 

im thinking of monitoring the input signals and power, also the outputs to the valve and see if anything changes when the fault happens firstly. 

 

 

thanks but definately not going down the carbs route !

[2400man]

12 hours ago, cam.in.head said:

hi.   motronic is a different system completely ,but it does contain the idle regulation all in the same ecu .along with ignition control as well .

ive watched that video. a couple of failing caps seems to kill them . i did try changing my caps ( 5 electrolytics) but no difference.   my next step is possibly to replace the entire jetronic loom ,the main ecu and the ignition ecu just incase anything there is killing them initially ? 

however ,once i find the actual failing part in the idle ecu al should be we.. 

im thinking of monitoring the input signals and power, also the outputs to the valve and see if anything changes when the fault happens firstly. 

 

 

thanks but definately not going down the carbs route !

Here's what my mate Adrian has come back with after seeing the pics of the ecu internals. Hope this helps:

Without knowing how it works, or what any specific component does but knowing the units fail after time my line of attack would be to:

1. Replace all of the Electrolytic capacitors – ringed in blue but reading the notes that’s already been done.

So then I guess I’d:

2. Check out all the higher powered transistors and their associated components (driver transistors and resistors and diodes) outlined in yellow. I’d remove the transistors from the board, check them on a tester and whilst they are out of circuit measure the resistors and check diodes.

3. Try using some freezer spray around the board bit by bit to see if there is a component that is failing due to age/temperature stresses. 

4. There is a large white block – I cannot see any component markings – I’m assuming it’s a capacitor and not a relay.

   [It's marked C9 on the board so I presume a capacitor]

5. The 14 PIN DIL chips are all Op Amps and obtainable I reckon, the 8 pin DIL is a Comparator which might be suspect, but again components around it could be at fault, there may be Zener diodes used to set reference voltages which could have aged.

That’s the best I can offer I’m afraid.

The good news is that they are all discrete components, and the resistors appear to be high tolerance metal oxide types which is good news.

 

 

[®evo03]

Great to have services like this still going, and able to fix. Sounds positive and interested in helping. 

[cam.in.head]

thankyou for the above information. yes i have changed the electrolytics, the pictures were from before i did that.

i will now change the large white capacitor and check the transistors out of circuit. if nothing shows up 

after all this i may rig up an led light check board and couple it to various inputs/ outputs and monitor whilst using the car. as mentioned these can work ok for a while and go faulty once in a journey or be ok for days on end.

if i monitor input voltages to the supply,(neg and pos),throttle switch input,tacho input and the double output to the valve inc common i will hopefully see something drop out when the fault occurs, 

this will not beat me.  thankyou so far for everyones reply.

[2400man]

18 hours ago, cam.in.head said:

thankyou for the above information. yes i have changed the electrolytics, the pictures were from before i did that.

i will now change the large white capacitor and check the transistors out of circuit. if nothing shows up 

after all this i may rig up an led light check board and couple it to various inputs/ outputs and monitor whilst using the car. as mentioned these can work ok for a while and go faulty once in a journey or be ok for days on end.

if i monitor input voltages to the supply,(neg and pos),throttle switch input,tacho input and the double output to the valve inc common i will hopefully see something drop out when the fault occurs, 

this will not beat me.  thankyou so far for everyones reply.

Good luck fella. You'll get it sussed for sure.

[gt4_ade]

i have used a a gte style one before with a dc motor controller and pot to adjust air bypass on the fly

[cam.in.head]

the gte one is basically just a heated electric valve which is either open or closed after time . thats a last resort to go gte style but at least it will probably be more reliable.

however !

mine has behaved itself after my last session on it ,replacing capacitors and resoldering joints. i have also added  a washer / air restrictor in the hose as suggested by mr sutty so that when the ecu throws its toys out of the pram the revs only rise to around 1000 rather than 3000.!

and ive sussed out which resistors to change to alter idle speed so that will open up my replacement ecu choices in the future .

[2400man]

On 22/01/2024 at 22:17, cam.in.head said:

the gte one is basically just a heated electric valve which is either open or closed after time . thats a last resort to go gte style but at least it will probably be more reliable.

however !

mine has behaved itself after my last session on it ,replacing capacitors and resoldering joints. i have also added  a washer / air restrictor in the hose as suggested by mr sutty so that when the ecu throws its toys out of the pram the revs only rise to around 1000 rather than 3000.!

and ive sussed out which resistors to change to alter idle speed so that will open up my replacement ecu choices in the future .

Sounds like you've made some good progress there by replacing capacitors etc and sussing out the resistors 👍

[cam.in.head]

i hope so . time will tell . 

the electrolytic capacitors were the first port of call because  of there age and periods of inactivity can dry them up . however caps from the 70's and 80's were very good quality anyway so wasnt sure .possibly why it didnt seem to change anything . maybee there was a bad joint that wasnt visible ? and has since been resoldered ? every cold  start now is limited to 1200 rpm anyway . 

thankyou to everyone for their help and advice 

[Jessopia74]

1 hour ago, cam.in.head said:

i hope so . time will tell . 

the electrolytic capacitors were the first port of call because  of there age and periods of inactivity can dry them up . however caps from the 70's and 80's were very good quality anyway so wasnt sure .possibly why it didnt seem to change anything . maybee there was a bad joint that wasnt visible ? and has since been resoldered ? every cold  start now is limited to 1200 rpm anyway . 

thankyou to everyone for their help and advice 

That is encouraging then, as you say the caps are common on ECU refurbs, and whilst it’s an analogue circuit, still a good place to start. I do perhaps wonder though if it was more dry joint(s) on this particular PCB but not always? 

Good progress imo, so worth a go at repairing the others you have to see? 

[cam.in.head]

i wish i still had the others ! 

that was many years ago . i got my first 2.2 in 1994 and have binned a few ecu's since then. only got the 1 spare now i bought off a member here which MAY be fixed ??

[Jessopia74]

3 hours ago, cam.in.head said:

i wish i still had the others ! 

that was many years ago . i got my first 2.2 in 1994 and have binned a few ecu's since then. only got the 1 spare now i bought off a member here which MAY be fixed ??

Ah, thought you had more in possession. That is a shame, but worth having a try on the other one too.