Serious (fire Risk?) Aircon Problem (vq37vhr)

[talkiet]

I have a 2009 Skyline crossover (370GT) and yesterday I was happily driving along with the airconditioning on and the car seemed to hiccup a couple of times and as I pulled up to a red light it stalled... I restarted the car and immediately heard a strange noise that sounded like (for some reason) the AC compressor? I flicked the Aircon off and the noise immediately stopped and the car carried on fine...

Pulled off onto a quiet road and with the car sitting still in park, I turned the AC on again... There was a cyclic noise, a bad noise - and the engine revs dropped significantly in time with the bad (graunchy) noise - every 3-4 seconds...

Turned the Aircon off and drove home with no issues at all.

I popped open the bonnet today and turned the engine on (again, in Park) and no issues - but when I turned the AC on, it again made a horrible noise... By the time I got out of the car and around to the front to look and see if I could see anything (fat chance with how tightly it's all packed in) there was smoke coming up from the front of the engine. Dived back inside and killed the engine of course.

The smoke was not oil smoke - it smelled acrid - like burning plastic or rubber.

Does this sound like a toasted/seized AC compressor? If that's the case, what am I up for? New compressor, system recharge and possibly a new accessory belt + some labour?

What else might it be? I'm probably going to take it in tomorrow to have someone look at it but if there's a common failure or conventional wisdom on this then I'd love to be prepared.

I'd hate to think what may have happened if I hadn't noticed the noise and turned off the aircon within 4-5 seconds of noticing the noise/smell each of the 3 times it happened.... It took no time at all to generate significant amounts of smoke. (FWIW - I do have a fire extinguisher in the car beside the spare wheel and one on the wall of the garage about 5 metres from where I was standing)

Cheers - Neil G

Edited April 17, 2016 by talkiet

[sonicii]

it does sound like a seized compressor, the smoke would have been the slipping belt, much longer and the belt would have likely just snapped.

As for the repair.. I would guess at minimum you would be looking at a new compressor, and I would replace the belt too, then a leak check and gas recharge.

At worst, the failure could have pushed metal fragments through the AC system and the whole system could need to be flushed and some other components possibly replaced if they can't be properly flushed out.

[talkiet]

Thanks for that... It was only the last of the three events where I saw smoke and the other 2 were definitely still producing some AC - it was pretty clear there was some movement in the compressor - it was slipping, not seized... It may we have completely seized now though with the last one. I'll throw it at a professional tomorrow and hope for the best - thanks for the quick confirmation I'm probably on the right track at least.

Cheers - N

[talkiet]

Ouch - just had a look at the cost of a new compressor from Japan... $900 USD excluding the clutch, $280 for the clutch. I wonder if I could get incredibly lucky and it just be the clutch that has failed?

Cheers - N

[KiwiRS4T]

Where are you? Second hand compressor a possibility?

May just need bearings.

[talkiet]

Down in Christchurch... I'll take it to a specialist Aircon place I think instead of Nissan and try mu luck that way.

Cheers - N

[The Max]

From what I've seen in the past on similar issues, it's most likely the bearings. If it were clutch, the A/C would never engage and that pulley would continue to rotate freely. The fact it only seizes when the A/C is on means the clutch is engaging but the bearings are probably locked solid.

But that's just a best educated guess. You'll find out when you get the report back from the A/C guy. Good luck!

[talkiet]

I phoned an aircon place this morning and described the symptoms in detail... The guy said that his first guess was the bearings either badly on the way out or actually locked solid. Hopefully it hasn't blown up the entire pump...

I'm dropping the car off in the morning and for the sake of completeness I'll update when I have a diagnosis

Cheers - N

[talkiet]

Ugh... system degassed and drained. There is a small amount of crap in the fluid and the bearing is fine... The resistance is coming from the compressor itself. So they are looking for a replacement pump and I am steeling myself for a significant expense :-(

Fortunately the car is still perfectly usable in the current state and the pressure interlock means I can't even accidentally turn on the AC pump, but I can still use the heater ok.

Cheers - N

[The Max]

Bummer. It's easy to keep the A/C from engaging accidentally in a worst case scenario anyway ... just unplug the electrical connector which engages the clutch.

At any rate, not the best outcome but shit happens with these money pits called cars.