Thanks for that, but i have just ordered a NTK 25005 sensor for $45 shipped. Might be a risk, but i will give it a go. If it doesn't work i will have to get the $180 one. Part is due on the 24th, i will report back if all goes well. Thanks all for your help, if feels great to have this car running s...

Its a 10V car. Unplugged front O2 sensor toady, idle was a bit high but it ran great. Plugged it back in, idle went back down under 1000 car ran like puss again. Looks like this should be the last sensor. I checked the resistance values of the ETC sensor, at 25 it was around 2200, so seems right but...

Should i replace both front and rear?
Can i run with these unplugged, dose the engine use a default value like it dose with other sensors when unplugged?

The TPS i used was bosch, the ECT was Hella.

Tested fuel pressure at the injector rail and it shows 34 with key on, 38 - 40 with engine running, fluctuates around 2psi while revving.
Test was done with my air compressor so may not be perfectly accurate.

Thanks for the response Niel. Plugs are NKG R B4R6EKUB, they have 2 prongs? Leads are FML. Cap is Bosch. I was going to purchase this kit. https://www.fcpeuro.com/products/volvo-tune-up-kit-cap-rotor-plugs-wires-non-turbo-oem-voltuneupkit1 There are 2 connectors mounted under the cap, one has a flat...

Well dead cold running was smooth, but it now dose not take long to heat up and start running poorly. From a stop it struggles to get going, sounds like it might stall, no backfires just spluttering. Once the revs get up a bit it pulls smoothly. Talked to my volvo guy he said replace the IAT, removi...

(wow thats a big story. here is a TLDR) Runs rough when hot from stop at low revs. Pulls great from 2-5 smooth. pulled MAF, no difference. Cleaned IAC and throttle body. Replaced TPS, thermostat, ECT, voltage regulator. Can read and reset codes. Hi all. long time lurker, first time poster. Your help...