Should you need a Volvo specialist vaguely near you (Surrey - but where?), GB Autos in Worcester Park are worth a punt - reasonable prices and a bona fide Volvo nerd! Ask for Glenn or Tom

Good luck

Ah the joys of old cars. I figured a break from cycling to work this morning, and figured 'Grace' (as my 240 is now called) could waft me to work...

Well not really. Started fine, then the dreaded rough running within 20 seconds. Terrible to drive with no power, rough idle, next to no acceleration etc etc. 2 miles later, nearly perfect!!

Got some days off next week and I think I'll start playing around the ECT sensor and so forth..

Why would you want a break from cycling? Rider and road in harmony. Especially in winter, I do mean that seriously. Deep joy.

You seem to know a lot mre than me about the 240. But it sounds a litle like MAF. How are the code reader results and other tests? Can you borrow a known good MAF for a while? Please don't buy a new ne unless sure of needing it.

Good luck.





You do have winter cycling boots? And mittens? :)



.

Super keen cyclist, just not feeling it this morning at 0445hrs before work.. Fully equipped for year round, MW81 boots down to 0 degrees, Northwave below that.

No codes FWIW, I've done a fair bit on the beast the last few weeks in terms of fault findin, MAF and O2 are OK, TPS and ICV all tested/cleaned etc as OK. Throttle body done.

I reason that since the ECT sensor advises the ECU of engine temperature, and as a consequence fuelling, that if it is a bit iffy it will assume the engine to be warm (read that somewhere) and fuel accordingly. I think this would give my symptoms as it would be under-fuelling until the engine is actually warm.

I'm going to do some testing when I get the time off, but will likely order a generic new ECT sensor like this one:

https://www.ebay.co.uk/itm/Fits-Volv...53.m1438.l2649

Well after the usual lumpy start, all went well on the way home until sitting in traffic waiting for the level crossing to open. Bing! On comes the engine management light..
A quick black box read when I got home, 1-1-3 injector fault. I've had this before and it cleared after sorting the ICV and stuff.
Ho hum, more to fiddle with, keeps me occupied I guess:teeth_smile:

A spare hour before work left some playtime.

With my knuckles now suitably skinned, I think perhaps the ECT sensor may be ok. Connector removed, and after standing all night I got 8.5k Ohms. Running for 5 mins on the drive and measuring again gave me 0.4k Ohms. Not entirely in spec, but it is behaving correctly.

Next step was to check pins 5 & 13 at the ECU. What a PITA that is to get at and unplug. Anyway, no idea which pin is which, they are not numbered on the plug and you can't trace the wiring to each pin. I ended up testing every pin to every other pin, and at no point got anything like the readings I was seeing on the ECT sensor (which was slowly increasing in resistance as the car cooled). Maybe a broken wire I don't know.

Does anyone have a picture of the ECU connector showing which pin is which? I've searched to no avail.

I’ve got a copy of the wiring diagram for a late 240 with 2.4lh, send me a message including your email address and I’ll send over a copy.

I think the pins might be numbered inside the plug, if you peel back the rubber bootie and undo the two screws under it, as well as the single screw at the other end the plug can be separated into two halves- the pins are all secured so they won’t randomly all fall out.

Cheers

What an interesting thread - full of useful information.
Alan

How very frustrating. After typing a PM to your good self, I'm told I need 30 posts before I can send a PM. I'm off to make 10 meaningless posts elsewhere!

Thanks for the PM, I've sent you an email. Cheers