Hey everyone...

I started noticing this problem at the end of last summer on a few hot days and didn't fix it. Well summer has finally arrived in MN and I'm running into this problem again and it has me a bit nervous.

On hot 90 degree days, if I am driving at slow speeds or stopped with the A/C on, the temp gauge starts to spike and the A/C turns off. This is not good because I'm sure its terrible for the engine and I spend almost the entire working day in my car. I need the A/C to work and I also need to avoid blown head gaskets, etc.

I had a similar problem with my last Jetta, but it was much more sudden and the problem was much worse. I put in a new water pump and everything was good to go again.

Anyone else have this problem? Let me know?!?!

 

Have you changed your coolant? If so, did you follow the procedure to make sure all the air is out of the system? Just a small bubble could cause havoc when temps soar.

What about the condition of the radiator. Is it clean? Lots of fins bent? Every sprayed it out?

Have you verified all the cooling fans are coming on?

 

Coolant was just changed recently, and I took it back because it had bubbles in the system, but those have been purged. Problem is there there.

I've never really looked at the radiator. I keep my car pretty clean but I can check to make sure.

The fan right in front of the engine comes on, but I can't seem to tell if the one on the radiator is or not.

 

Might be as simple as a bad thermostat. Have that checked out, water pump issues on the G are fairly rare.

 

Who did the work? The Nissan procedure to completely purge all bubbles is lengthly and takes lots of driving, checking, purging, warming up, filling, etc. Reverse-flow cooling systems are notorious for being hard to clear all bubbles.

 

I had a Nissan dealer do the work. The tech I spoke with today from that dealership thinks that my A/C unit is at fault. To test his logic, I drove around for awhile in the 100 degree heat and 100% humidity (lovely experiment) for 40 minutes and had no issues with the temp of the car at all. Today the A/C was not coming out very cold and would sporadically go out and blow warm air.

I suppose it could be a sticking thermostat but I am starting to think the A/C unit is the culprit here.

 

I only ran my car til it got hot a few times while I was trying to figure out the problem and it's now costing me over $2000. Our heads are aluminum and canNOT take very much heat...be careful and get your gaskets and heads checked before it's too late

 

ouch!

 

ouch!

 

Clean the a/c condenser. Car wash, high pressure hose and spray the hell out of that boy. Local guy had some problems you are having, and after 15 mins in car wash bay, that issue is gone.

 

reverse flow systems? are you saying that this setup pumps thru the thermostat into the lower rad hose thru the radiator then out of the top hose?

 

^Since you're in Australia, the G... I mean skyline, has a forward flow and all other cars have a reverse flow


J/K


I believe what Dave was talking about is a coolant system that pumps directly to the heads first, then to the block/water jacket.

Not 100% positive though.

 

Typical cooling systems cool the block, then the heads.

Reverse flow cooling systems cool the heads first, then the block. This is typical of high compression motors.

I wasn't aware the VQ35 was reverse flow, good to know...