Rough idle

[gargray]

I am having issues with rough idle and car goes into limp home mode
Model 1999 Volvo s70 100k miles

I bought a obd 2 code reader and it is throwing codes

P0645
P1620
P1081
P1026
P1031
P1017
P1021
P1026
P1031

I am using the action cp9125 reader is there a conversion from p codes to Volvo dtc codes?

I read on the forum that the maf may be the issue. I replaced it, and it didn't fix the problem

Pulled the etm fuse and etm would whine but not seem to shut off. Replaced fuse to etm started car and car ran fine until it was shot off and restarted. It then went back to rough idle and limp home mode

Wanted to confirm it is the etm before I replaced it

Thanks

[midniteliquid]

P0645 -- Air conditioning (A/C) relay -- Signal missing

P1620 -- Engine cooling fan low speed -- Signal missing

P1026 -- Throttle Body Internal Fault

P1081 -- Fuel immobilzer fault

P1031 -- Heated Oxygen Sensor -- Heater Current Monitor Control Circuit (Banks 1&2, Sensor 1)

P1017 -- Engine Control Module (ECM) internal failure

P1021 -- Electronic Throttle Module (ETM) fault



I would make sure all of the ground connections are good, but it looks like the ETM has gone bad and is causing other errors because of the incorrect fuel mixture.

[98T5]

I have a rough idle but only at stops so I'm guessing mine is an incorrect starter. I have a Regina ignition system and a Bosch starter. I heard the two don't cross integrate well. and since I've fixed everything else that could cause a rough idle: dirty TP sensor, dirty intake, dirty IAC valve, plugs, wires, rotor and cap, it MUST be the starter mis-match that's causing my problem. but G'Luck with your issue as well.

[98T5]

turns out my rumble is coming from bad motor mounts