Intermittent engine light

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SonicSW20
Posts: 3681
Joined: Mon Nov 29, 2010 7:54 pm

Re: Intermittent engine light

Post by SonicSW20 »

That'll do it.

Has the fluid damaged any traces? If so you may need to put some jumper wires on there too.
DaveWS
Posts: 34
Joined: Sat Oct 01, 2016 7:09 pm
Location: Leicester

Re: Intermittent engine light

Post by DaveWS »

SonicSW20 wrote:
DaveWS wrote:I tried that, basically the engine light flashes constantly at first, and then the light turns solid (matching it turning on when not in diag mode). It doesn't throw up a code :(

Weirdly if I remove the paperclip with it running and reinsert it again, the engine rpm picks up for a few seconds then bogs right down to 600rpm or so. :-k I guess the diag mode is only for when the engine is off because it seems to mess with the fuel mix or something.


Diag mode is used to set ignition timing, it puts the timing into static mode so a drop in RPM is normal.

Clutching at straws really... Have you removed the ECU and taken the cover off to inspect the board? They're at that age where capacitors fail which can cause all sorts of odd issues.


Yeah I already opened up the ECU and replaced both 10mF capacitors to fix another problem months ago (engine wouldn't start when hot) - I also had to repair a corroded trace.

I've inspected the rest of the ECU pretty closely and I don't think there's any further damage, but without another working ECU it's hard to know for sure. :-k
Pauln
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Joined: Mon May 08, 2006 10:15 pm
Location: Cardiff, South Wales

Re: Intermittent engine light

Post by Pauln »

Long shot, but it's a double sided PCB, did you solder the capacitors on both sides?

Paul
DaveWS
Posts: 34
Joined: Sat Oct 01, 2016 7:09 pm
Location: Leicester

Re: Intermittent engine light

Post by DaveWS »

I opened up the ECU again today and added several more jumper wires to every connection which might have looked even a tiny bit suspect (even though continuity was fine). Still the same :(

Could it be an earthing issue somewhere?
DaveWS
Posts: 34
Joined: Sat Oct 01, 2016 7:09 pm
Location: Leicester

Re: Intermittent engine light

Post by DaveWS »

Checked and cleaned several earth points in the engine bay area and still the same problem. Anyone know of a used ECU for sale? Just so I can rule it out. P/N is 89661-17380. There's one on eBay currently, I've messaged the seller to ask about the caps...

I also think this fuel pump relay must be related somehow. It switches on or off when the engine light turns on. I can't find any over here for sale though. P/N is 28380-74050
SonicSW20
Posts: 3681
Joined: Mon Nov 29, 2010 7:54 pm

Re: Intermittent engine light

Post by SonicSW20 »

FP to B+ in the diagnostic port bypasses the relay doesn't it, and just supplies full power to the pump at all times? If thats the case then you can do that and see if the problem persists.
DaveWS
Posts: 34
Joined: Sat Oct 01, 2016 7:09 pm
Location: Leicester

Re: Intermittent engine light

Post by DaveWS »

Hmm, just tried that and it makes the relay go nuts, makes a screeching sound. :?

Tried disconnecting the relay completely with the jumper trick, car starts and runs, but sure enough after 10-20 seconds the engine light still comes on! ](*,)

I bought that ebay ECU, so will swap that out in a few days time and see what happens. Christ this is something else lol
SonicSW20
Posts: 3681
Joined: Mon Nov 29, 2010 7:54 pm

Re: Intermittent engine light

Post by SonicSW20 »

The relay makes a screeching sound? :shock: That doesn't sound right, but at least that test rules it out as being the cause of the EML issue.

I can't understand why there's no code stored though.
DaveWS
Posts: 34
Joined: Sat Oct 01, 2016 7:09 pm
Location: Leicester

Re: Intermittent engine light

Post by DaveWS »

Replacement ECU arrived and installed, and no engine light! No idea what could still be wrong with the old one then, I've repaired all the traces that look remotely damaged and replaced all the capacitors which I had spares for.

Thanks for all the help in this thread, I would have gotten a replacement ECU sooner but there were none about until just a few days ago.

I've also still got an intermittent horn (mostly doesn't work but occasionally does!) to fix...
ribbo
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Location: Southampton
Contact:

Re: Intermittent engine light

Post by ribbo »

DaveWS wrote:
I've also still got an intermittent horn (mostly doesn't work but occasionally does!) to fix...


*innuendo claxon*
DaveWS
Posts: 34
Joined: Sat Oct 01, 2016 7:09 pm
Location: Leicester

Re: Intermittent engine light

Post by DaveWS »

Haha very good.
SonicSW20
Posts: 3681
Joined: Mon Nov 29, 2010 7:54 pm

Re: Intermittent engine light

Post by SonicSW20 »

At least its sorted! Yeah, Gen3 3SGTE ECU's don't come up all that often and people often want silly money for them.
DaveWS
Posts: 34
Joined: Sat Oct 01, 2016 7:09 pm
Location: Leicester

Re: Intermittent engine light

Post by DaveWS »

Bump - I've started another thread because I still can't fix the fecking horn :( forums/viewtopic.php?p=1708203
markstevieandmads
Posts: 2025
Joined: Mon Aug 05, 2013 8:18 pm
Location: Swindon, Wilts

Re: Intermittent engine light

Post by markstevieandmads »

SonicSW20 wrote:At least its sorted! Yeah, Gen3 3SGTE ECU's don't come up all that often and people often want silly money for them.


his ecu was a rev 2 turbo according to that ecu number. Even more common for the caps to blow
hojoos
Posts: 19
Joined: Sat Jan 18, 2020 2:40 pm

Re: Intermittent engine light

Post by hojoos »

Could be lambda related?
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