LH-2.4 ECU required for 94 N/A 940

ShKa

Dear all

I'm needing a WORKING ECU for my 94 N/A 940 ..

Can anyone assist?

ECU numbers compatible are apparently 0280 000 935/ 954/951/946/943 but these are numbers lifted from Volvo UK forum .. my ECU -which I think is stuffed -ends 777 so no idea where that one comes from! (unless previous owner changed it or something)

cheers

Major Ledfoot

ShKa my ECU -which I think is stuffed -ends 777

There's a Volvo part number that ends in '777' - it's actually 3547777.
Its Bosch part number is 0 280 000 935.
This is for a B230FB engine from 1992-95.

ramrod

What makes you think your ECU is faulty?

What’s the story? (Long answer)

What kind of problems are you experiencing?

ShKa

ramrod

Bought the 940 as a misfiring project.

Difficulty starting , rough idle, black fouled plugs , no power on shifting into gear, stall . Fan comes on immediately and runs all the time.

Lambda light etc all on at time of purchase.

Compression poor cylinder 3 - broken piston ring - block and head then rebuilt all new stuff.

Compression good and equal.

Timing correct , flexplate correctly orientated. Temp perfect.

Every sensor , AMF, injector tips/ seals. fuel pressure regulator, dizzy rotor , ignition coil replaced

Engine codes show AMF good, stepper idle , fuel injectors , fan all working(altough it still runs as soon as I get it started. And starting remains a pain. 10 attempts before it might splutter into erratic life.

Lamba light remains on.

Issue remains the same.

Im done wasting time.

Im nowhere near any auto electrician and any that might be around 100 miles from here (UTEville) will know zero about old Volvos.

So basically Ive remedied all I can .

Hence Im thinking it maybe needs a new brain.

ShKa

Major Ledfoot Ah - thanks

ramrod

You need to isolate the problem on a deeper lever and figure out what’s missing.

Is the spark plug lead order correct? (firing order) you mentioned there had been work done in this area so verify it is correct.

Is the camshaft timing correct? (Is engine timed correctly) you mentioned previous work done in this area so that’s important to verify.

What’s the fuel pressure?

Does the engine seem happy to idle? Do all four pistons fire in harmony? Perhaps share a video of what it runs like.

Does the engine respond as it should to throttle input? Does it drive okay? Is it able to accelerate? Have you driven the vehicle some distance?

Is there smoke from the exhaust pipe?

Has the cooling system been pressure tested?

There are more questions, but not before these ones have been answered.

ShKa

ramrod

Thanks for the advice.

ShKa

ramrod

so looking at more detail in response to your suggestions-

spark plug order looking at dizzy from front of engine is left to right is 4312.

Timing - yes I think that is correct. I have lined everything up correctly but I need a timing light to confirm 100%

Fuel pressure - static = 37 psi , idle (vacuum) = 35-37 psi idle (no vacuum) = 43 psi BUT when engine is revved - fuel pressure DROPS to around 33 psi

It takes about 20 attempts to get it started..then idles roughly. if I rev it , the take my foot off , it stalls and stops.

Engine revs freely when throttle pressed -once I get it going/ warmed up.

No smoke from exhaust.

All sensors been renewed.

OBD check functions : with sensor placed in hole 2 , code 1 flash pattern is 111 and fan , stepper valve and injection all comes on .

OBD hole 6 - I get pattern 334 -which I believe means TPS is OK

When I check code 2 and code 3 - rapid flashing lights come on.

Ideas ? lol!

Evan11509

There's a '951 for sale on eBay in Western Australia.

ShKa

Evan11509 cheers

jamesinc

I might have something, if you're still looking send me a DM

Anthony

Crankshaft position sensor ?

(Apology if you mentioned it in your list)

Anthony

Quote: spark plug order looking at dizzy from front of engine is left to right is 4312.

Timing - yes I think that is correct. I have lined everything up correctly but ..,,

The more correct answer is:

Right to Left 4-3-1-2. Right being the brake booster side for RH drive. Pic attached.

Fix this and it might just start!

Image description

ShKa

Anthony

Yes- that's exactly how mine is. 4-3-1-2 from left to right looking at it from FRONT of engine bay with 4 being next to brake booster. You can say 4-3-1-2 from right to left if you like if you are sitting in the drivers seat! Each to their own 🙂

jamesinc

Given the symptom and the new sensors, is it possible you have an LH-2.2 engine coolant temp sensor instead of 2.4? They're incompatible, but physically identical, except 2.2 has a blue connector, and 2.4 has a black connector.

ShKa

jamesinc I have the black connector .

ramrod

So what I’m understanding from your explanation is your engine seems to respond and run satisfactorily once it warms up.

If that’s the case, does it idle? Any complaints with the way it drives once it’s warm?

Is this a cold running and starting issue only?

ShKa

ramrod Its more complicated than that. it will "drive" but stall and backfire when slow and when I press the gas.. BUT if I shift into gear 1 or 2 as opposed to D , it will rev and drive. I can't drive it around as no plates at present. And fuel pressure goes DOWN when I rev it . Reading up , could be radiosuppression/ fan relay-which weirdly control the injectors apparently and can do exactly what Im describing, fuel pump relay, fuel pump , blocked fuel filter (unlikely as new ). Would like to just try a new/working fan relay but can't seem to find any online these days . Ditto for the pump relay ( the wee blue one in the tray Volvo 9130270 )