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B21 Kjet low idle, no power, '78 242

Sorry, Ian, didn't mean it as a critique. We in the 49-state arena didn't get lambda-sond until '80. Indeed, the book (NCF 78) does show the two systems as if they were separate.

No need to apologize Art. ;-)

If you want to "restore" the car, yes, get a new plastic housing. But you can make it reliable with new terminals crimped on wire cut back to where it isn't crispy even without a new housing. I think Dave Barton has the sockets on hand, and I bet Ian and Eric can find one for you too.

Yep, Dave has them for $3.

https://www.240turbo.com/blackvinyl.html#5polerelayplug

They cost less from Volvo but who knows how long it will take to get one.

https://www.tascaparts.com/oem-parts/volvo-insulator-964198
 
Scroll down 2 items for the relay insulator. That's the closest anchor to the fuel pump insulator on Dave's page.
 
Ok, so I replaced the fuel pump relay socket and relay, as well as the Lambda Sond relay. The idle air motor? plug was all smashed up, so I replaced that as well. Big thanks to Dave Barton for his patience and for stocking this stuff for us! New plugs, Bougicord wires (except had to get aftermarket coil wire), cap and rotor. Plug wires properly routed instead of a zip tied bundle. The engine sounds a lot smoother, cold idle is now 1100 RPM. Exhaust is still incredibly loud and leaky haha.

First impression is that the car is still very slow. I was only able to do about 4 miles in it, I hope to do a lot more tomorrow, and hope the exhaust doesn't get me in trouble. The good news is coming up the very steep hill to my house, in second gear the car now revs much higher, was 3k rpm, I hit a bit over 5k rpm. There is a lot more power after 4000 rpm for some reason (the VX cam? idk). But shifting to 3rd at 5k rpm, no torque and I had to go back to 2nd gear.

I didn't get to check the warm idle, it didn't get very warm. Hopefully an update tomorrow.
 
Maybe I am ordering from the wrong place haha. I got a Volvo box with 4 wires in it and contacted them, they sent me the proper length coil wire, it just isn't a Bougicord.

I still haven't been able to take the car out yet, I will definitely update after I do.
 
I got to spend some time behind the wheel today, I was held up due to a small u-joint fiasco but its fixed now. Anyway, here is how it went.
Cold start, takes a couple tries and it fires up. Power sucks worse than normal with the engine cold, hesitates. Got somewhat better after it warmed up. 1st and 2nd gear are really slow and the RPM's build slowly. The only way to get any decent power is to shift 6k rpm, and keep the revs high in the next gear.
I got it up to 75 MPH (not an easy thing to do, really revving it out), then I had to slow down, dropped back to 4th, and struggled to get back to 65.
Warm idle is still 600 RPM.
I did not get a chance to check ignition timing yet due to the u-joint stuff, ran outta time, but we did get a test pipe in where the cat used to be. Its mounted with some pretty stiff rubber, and vibrates the car a little...

Looking at my Haynes manual, the first thing it says is the idle speed needs to be correct, which mine isn't, but not sure if I should adjust it.

I will recheck the Lambda system again, I did not go through all the tests again after fixing the fuel pump relay issue, there may still be a problem somewhere.
 
Your description of how the car drives is how an old kjet car I had acted when it had low fuel pressure. The pump on the car was intermittently failing. The pump pressure would drop after a few minutes of running but not low enough to make the car stall. It would drive like it had no acceleration. When the pressure failed it was something like 45psi system pressure instead of the proper 65-70psi.
 
I was wondering about the fuel pressure also. The pump underneath looks new, but it's black plastic so probably a piece of junk. Everything I have seen about testing the fuel pressure looks like a pita with non available tools. Might be easier and less annoying to just replace the pumps.
It may have been pretty hard on the pumps when the relay was arcing, turning them on and off quickly a million times in a row...
 
I would definitely be interested in renting the tool, I don't need to own one, since I decided that this car is getting a full build and that will not include KJet...I would like to get it running well first since I want to drive it as is for a while.
 
I rented the tool, should be here soon.

Today I installed a wideband, and it is running so lean under even light acceleration the gauge is pegged on lean (18 is where it stops, so I get --- on the gauge)
I'm installing an in tank pump because it's cheap and easy, hoping it will help. I'm looking around for a decent in line pump since I don't think the car can handle the 340 lph pump I have on the shelf. Hopefully the problem is not in the mess of crap under the intake manifold haha
 
Got the fuel pressure tool, hope to use it tomorrow. I threw new fuel pumps in, which made a fractional improvement. Now the wideband can read the afr at part throttle, at the very leanest edge of lean. Full throttle is still over 18 though.

The frequency valve thing is not working apparently, no vibrations or noise from it.
 
Got the fuel pressure tool, hope to use it tomorrow. I threw new fuel pumps in, which made a fractional improvement. Now the wideband can read the afr at part throttle, at the very leanest edge of lean. Full throttle is still over 18 though.

The frequency valve thing is not working apparently, no vibrations or noise from it.

Check the frequency valve socket, I had some issues with that before I Frankenstein:d my car. I could shake it and it would work, it wasn't making contact inside the socket. I replaced it with a parts store socket and it solved my problem.
 
Thanks, the socket had a very damaged terminal. I spliced a B230 fuel injector plug on to replace it. Cooling off for a few then back to it.
 
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