volvo 440 (b18u)

help my car keeps cutting out every time i drop the cluch,ive changed the idal speed control unit,ive ajusted the throtal cable,ive even had it on a bosh tester and it told me there was an ECU falt so i changed that but still no good. has anyone had this problem if so help am almost ready for giving up

[night owl]

Check to see if you have a crankshaft position sensor, if you have take it off and clean it as these send signals to the ECU to control sparks to the plugs. Sometimes these get dirty on the sensor area and the signal of the timing mark can't be read and will fail to start the car or give a bad reading for timing and car will falter or stall. Just done one today on a 340 and 2 days ago on a fiesta because these were having trouble starting and now all seems well.

[Crispy-d]

Hi there, just wondered, would a 460 Turbo have one of these sensors. As now and again mine will judder at idle, revving at only around 500rpm, then with a few quick revs it will return to 1000rpm? I can't find this sensor.

Many thanks,

Crispin

[night owl]

It might well have one as most cars from the 80's - present started getting fitted with these. Another thing to check for is a dirty throttle position sensor (TPS) if one is fitted and the idle control valve (ICV) if one is fitted. Sorry I can't remember if the TPS and ICV are fitted for sure as it's been years since i've had my head in the engine of a 400 series, but hope this info helps. The CPS 9crankshaft position sensor) will be fitted either at the front of the engine by one of the pulleys with a wire connected to it or it will be at the rear of the engin fitted in the top of the bellhousing reading from the flywheel.

hi not 100% possitive on turbo models the two volvo's ive had have both been singal point injection and the (ISCU) is located on the front of the incection unit its a small black unit about 5cm long by 2cm high.........your best bett is to locate your throtal cable and were it conects to the throtal body on like a half moon rocker there will be something stoping the trotal from closing that should be the idal speed contral unit (ISCU)
I hope this helps let me know if you want ferther help :-)

[jlgrosvenor]

This sensor sits on top of the gearbox bell housing for the B18U engine.

After conducting major organ surgery on my B18U I am having starting/stalling problems. If I disconnect this sensor, and then connect again, the car seems to work again.

This is affecting the production of a spark because if you connect the main input lead for the distributor to a spare spark plug you have lying around, and earth it on the engine casing (rocker cover will do - and don't use your hands because it has some juice flowing through it), there is no spark when cranking the engine over after a stall. Fiddle around with the wiring for the sensor, unplug it and replug it, and the spark comes back again. Connect up the dizzy lead, and hey presto, the car works again - temporarily.

I am going to try cleaning the sensor. Failing that, a new one can't be that expensive. I will try Renault if I need one.

[geordiefella]

HI,

Just bought a crankshaft position sensor on monday from a volvo main dealer £30 & small change inc VAT, for a 96 440, didnt think it was too bad tbh.

My symptom was no spark therefore no starting. If you are able to resistance check the sensor first, it should be between 180 - 220ohms if its ok if its in the K ohms or M ohms then it'll be biffed!

Chris

[Paul240480]

Originally Posted by geordiefella

HI,

Just bought a crankshaft position sensor on monday from a volvo main dealer £30 & small change inc VAT, for a 96 440, didnt think it was too bad tbh.

My symptom was no spark therefore no starting. If you are able to resistance check the sensor first, it should be between 180 - 220ohms if its ok if its in the K ohms or M ohms then it'll be biffed!

Chris

IIRC it should be 220ohms +/- 60ohms. If it is out of this 'zone' bin it, if its within, as mentioned clean it.

For Idle control Valve see here: http://volvo480.dragons.org.uk/forum...ic.php?t=15569

Good Luck.

[Paul240480]

Originally Posted by Crispy-d

Hi there, just wondered, would a 460 Turbo have one of these sensors. As now and again mine will judder at idle, revving at only around 500rpm, then with a few quick revs it will return to 1000rpm? I can't find this sensor.

Many thanks,

Crispin

Meant to say Crispy-d yours will have the sensor. Same engine as my 480 Turbo methinks. With Turbos, its also well worth checking the turbo-pipes for air leaks. Just follow the pipes back from the air-intake, down to the turbo intake on the engine. Pray they are good cos at around £10 an inch they're pricey! The one down at the turbo intake does tend to rot where it joins the engine & is a right fiddly one to get to.

Also, just under the throttle body is a small length of braided hose, about 2" long. Give it a poke, may well be perished allowing an air leak. Mine just about fell to bits when I poked mine!