940 Start issues and rough idle

First of all hello to all of you! It's nice to see such a huge community dedicated to Volvos

A month ago I bought a '97 940 with turbo, B230FK engine, automatic transmission and it just had 126k miles on it. It also has a kme LPG system installed. I'm in love with that car! Loads of fun to cruise around with.
The first two weeks everything was okay but then issues arose.

Symptoms:
- cold start issue: takes approx 5-10 secs in the morning and it seems to struggle, it's easier when you step on the gas a bit while starting. works better when the car is warm and no gas needed for warm start

- rough idle: after startup it goes to 1k rpm and then gradually drops the next 1-2 minutes. sometimes it drops to about ~300 rpm or lower and catches itself again but it also stalled twice on me already. couldn't figure out a pattern, some days its better and some days its worse. what I also noticed is that the engine is shaking a bit.

Steps taken so far:
- cleaned throttle body (was nasty)
- cleaned MAF (also detached it while the engine was running and plugged it in again, the way the motor was running changed immediately when detached and I guess that means that the MAF is fine? at least it's not dead I guess)
- changed spark plugs
- checked on IACV but it seems fine, no major dirt/clogging and it moves just fine
- asked a friend to blow smoke into the engine room and look for vacuum leaks, couldn't find anything

It didn't get better yet. To rule out the possibility of the LPG system being faulty I also drove around on petrol alone and had the same issues.

What's next?
Detach the MAF and drive around it a bit to check if it's running better without it?
Check TPS and what to look for?
Check RPM Sensor and what to look for?

Looking forward to your responses and fixing the issue.
I don't have a lot mechanical experience but "working" on this brick is fun

Cheers
Hobo

Step 1 is remove the inlet hose to turbo and look for holes. Also the idle air hoses and intercooler couplers

Cheers.

ZVOLV said:

Step 1 is remove the inlet hose to turbo and look for holes. Also the idle air hoses and intercooler couplers

Cheers.

Click to expand...

Okay, I will check and report back. Thanks for the input

Any codes? Use the OBD box. I think it may store codes even if the MIL isn't on.

I use a smoke machine at the shop to find air leaks, but they can be north of $700.

Sorry for the late response, was quite busy the last weeks.

I managed to read the codes for the ignition and fuel injection system and both gave me 1-1-1, so no faults. I also checked for holes in the turbo inlet hose but nothing.
Yesterday I checked the MAF once again and unplugged while the engine was running, checked the RPM and it dropped to ~200-300. Also the lambda check light came on. I hope I didn't do any harm :/


EDIT:
Okay, just came back from work and checked the error codes again. It came back with 1-2-1 for Fuel Injection, which means MAF/o2 sensor. I also cleared the codes, started the engine and checked for codes again just to be on the safe side. Same error code, 1-2-1.
Next step would be changing the MAF I guess? Or is there something else to do beforehand?

By the way, can I just disconnect the MAF and drive like that until the replacement arrives?