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I have an intermittent problem with my Gen 2 Lib that I am having trouble tracking down.

I initially thought it was the fuel pump, but suspect it isn't as I thought it would just let go and not drop off for only a second at a time. Happy to stand corrected on this though.

So I think it must be in the electrical/ignition system somewhere, cuts out for about a second at a time. If it happens when coming up a driveway, ie low revs/changing down, the thing stalls and I get reds on the dash. If it happens at speed, the electrics keep running (ie dash backlighting on, no reds on dahs), and it eventually starts up again as the engine is still turning over. It's just like taking the foot of the accelerator and then putting it back on again a second later. Sometimes it won't happen in a day, sometimes 4-5 times.

I have tried the following things:
* Replaced the fuel filter.
* Replaced the ignition relay with the 2xBosch relay mod listed here on the forum.
* Checked the fuel pump relay. (Swapped the relay with the blower relay below it, but still happening. At least now that I know they are the same, a good thing to keep in the back of the mind in case I am ever stuck out on the road.)
* Ran the engine and fiddled with the wires/terminals in the engine bay to see if I could reproduce the problem. Was a suggestion in another thread here a little while back.
* Checked the fuel pump connections but everything appeared solid, and no visual contamination/degradation of terminals.
* Also replaced the knock, cam position and coolant temp sensors (long standing error codes).

Any ideas/suggestions gratefully welcomed.

Cheers, AJ.

I had the same problem with my Gen 2 Liberty RX.

Replacing the O2 sensor fixed it for a year or so but it came back and cleaning the MAF with some special purpose aerosol seems to have fixed it properly.

I'm thinking it's just the computer spazing when it gets confused.

is the car throwing any codes at the moment?

not sure if this problem is common to gen2 as well but in gen1 i would be looking at the fuel pump connector under the rear seat. just lift the seat cushion up and see if there is a connector under there. they commonly corrode and then burn out in gen1.

I'd be thinking air flow meter considering everything else that you have ruled out. You'll get one cheap from a wrecker and they are relatively common for causing cut-out with no fault code/other symptom on your model. We have done a few at my shop over the last 12 months. It's typical of the " hot wire" afm as opposed to the film
Style used in the my99-00 wrx which cause hunting idle and running rich rather than cutting out. I found that cleaning it had no effect on rectifying the concern on the majority of the hot wire type afms I've seen give trouble.

Grab a multi meter (a cheap $10 one will do) and extend its leads so they reach the last connector at the fuel pump. You will have to strip off just enough insulation to see the wire and wrap each of your extended multimeter leads around the stripped fuel pump wires and tape them up. Now each time you drive, monitor the voltage at the multimeter and if it drops at the same time as the car stalls, you know there is an issue there.

Thanks VV, I checked the fuel pump connector, even slipped some of the terminals out of the connector to check the join/crimping, all good.

No error codes at the moment.

I cleaned the AFM (CRC MAF cleaner) yesterday arvo, no repeat of the cut today, but as mentioned it doesn't happen everyday. The real test will be tomorrow, usually do about 100ks on a Saturday. Will let you know how it goes.

Cheers,

tip for you gannon. dont strip wires. use a sewing pin to pierce the insulation and jam into fhe wire. attach your probes go the pin, then tape it all up. you just pull the pin out when your done and there is no damage.

Last weekend I went out to Lithgow and my hopes were up on the way out there, but they were dashed on the way back when it started up again.

I managed to get to a wreckers on Friday to pick up an AFM, cleaned it also and swapped it over on Saturday morning. All OK until it happened again today around lunch. Disappointed, but at least ruling that out has gotten me one step closer to the solution.

Will try Gannon's idea over the next few days when I can find time after work. Thank you VV for the pin trick.

starts nice every time otherwise ? if so, sort of rules out fuel pump on its death bed, but who knows eh ?

We just brought Shorty's old Gen2 sedan that was always playing up on her. Turned out that the Cam Angle Sensor was not being very nice. It would work intermittently. After we replaced this, it hasn't missed a beat.