Hi all I just picked up a vx v6 on lpg its an ex general duties police vehicle and runs quite nice, just after a bit of help from you guys what I have noticed so far is 1) The car was running quite cold and one thermo fan doesnt even switch on ever. Once the AC is switched on the lhs fan starts but the other fan just will not goat all. Even with both fans off the car was running way to cold and the temperature was all over the place. Last night I flushed the radiator and replaced the thermostat, this seems to have fixed the problem as the car now reaches 91 then the thermo opens up and it cools to about 86 degrees then climbs and drops again is this normal? Remebering no fans are operating also. 2) The radiator always seems to need filling after every drive approx 600ml I cant see any leaks anywhere I have tried getting most of the air out and used the bleed valve on top of the thermostat housing but it still uses water also the overflow does not work its like the system has massive air pockets in it but I thought this would lead to overheating. Also no milky oil but radiator cap does always have brown gunk on it even after cleaning one day later gunk is back on it? Im thinking possible head gasket or cracked head but its not really showing any other signs? Opinions? 3) What is the best oil to use for this lpg vehicle with 200,000 klms as at the moment it is below the add mark and Im planning on dumping it out and changing it tommorow. 4) it also has vy ss seats with a vy ss steering wheel just wondering being a vx commodore will this pass rego as im unsure whether airbags etc will work the car does beep everytime you start it like the handbrakes up the previous owner said its because he replaced the seats and unplugged the pre tensioners with the battery connected. So not sure there. 5) What temp should a vx on lpg be running at and what temp is the thermo supposed to kick in at normally? Cheers all
does the airbag light come on? check to see if it does when you put ignition on, if it doesnt at all, someone has taken the globe out( just found that out on mine!) i got quoted $60 bucks by a local sparky to come and read codes and reset the airbag light. im keen to know about your cooling system questions my self.
Hi no air bag light comes on however when i hold mode and up button and start car in daignostic mode the last bit where its tests all guages I think the airbag light comes on is it the one with aperson sitting down with a steering wheel in front if so the globe does work but who knows what a sparky may have done to bypass it etc its just a long chime every start he reckons its the seat belt pre tensioners but who knows im not to worried as long as it will pass rego. As for the cooling issue it is a strange one its like there is jac **** pressure in the system i can also remove the radiator cap when pretty warm 80 degrees and water etc strange...
i had a VS that used to use water every so often. i suspect it was a head gasket. so i took the easy option and sold it! hahaha my VT had the long chime, but had no light on. after some friendly advice from here, i worked out it needed a globe. i put a new one in today, and it is lit constantly. have to get the codes checked now to see whrere hte problem lies. i been thinking about getting my own scan tool from ebay, that will reset the air bag light, but it seems that its not expensive enough to be able to read the SRS faults. thats about 80 bucks. might be worth it if i end up changing seats and what not in the future. luckily for me, im in WA, so we dont have yearly inspections. just pay the rego, and dont be a hoon on the roads and your fine!
it is the light with a person sittind down too. and i have read that if you disconnect the pre tensioners and turn the car on without them connected it will make the light come on all the time. could be a really quick and easy fix for you!
Probably need to bleed the cooling system, Oil on the cap is more then likely your intake manifold gaskets leaking.
Under normal operating conditions single fan operation is correct. Only with an overheat will the second fan come on. You need all the air out. Yes, a proper bleed is required. Use plastic bottle with the base cut off and electrical tape around the neck to seal in the radiator filler neck (or similar) to get the colant level above the bleed point. With LPG you will possibly have to run the engine so as to push any air from the LPG converter. If after bleeding the coolant level still drops, you will have a leak some where. One place less obvious is the heater core. Brown gunk is typical. Possibly (probably) the cooling system 'tablets' recommended by GMH to the seal the water pump. Head or head gasket failure on these engines is rare (but not impossible). Any of the dedicated LPG oils can offset the typically higher operating temps of LPG. Ordinary 20W50 changed early is an alternative. (recommended is 15W40, 20W40 or 20W50 SG or H). The (single) fan should be on at about 101C, off at 98C. Maybe a degree or two either side (I can't be bothered checking).
Hi Thanks for your help cheap 6 Im not sure about the fan as I have had the car up to 107 degrees and no fans turned on I have to manually put ac on for a fan to spin??? I also have chosen nulow 15w40 done the oil change this afternoon and no milky oil just black and thickish As for the heater core when I bought the car it did smell like its been sitting in a river however the heater works quite well. I noticed when i did the oil change today there was a bit of water towards the gearbox wasnt much I was just thinking ac drain hose???
107C is too high not to have at least one fan on. Looked the temps up: one on at 104C, off at 99C, both on at 112C, off at 108C. (Plus some A/C pressure switching.) The BCM switches the single fan, the PCM switches both fans. The PCM also transmits the temp. data from the coolant temp. sensor to the BCM. Did you get the temp. reading from the instrument cluster or a scan tool? If it's from a tool, then possibly the BCM isn't seeing a coolant temp. from the PCM.
FWIW, knowing how it works should aid a diagnosis. The PCM receives the analogue signal from the CTS, then transmits that as a digital signal (serial data) to the BCM for distribution to the instrument cluster. The PCM also signals, via serial data to the BCM, to switch on the low speed fan if the CTS voltage indicates that the temp is over 104C, then off < 99C. The actual low speed switching is by the BCM, the signal to switch is from the PCM to the BCM. The 'high' speed (two fans) relay switching is directly from the PCM to the relay. A/C request input and pressure signal voltage is to the PCM, then the PCM 'asks' the BCM to switch the low speed fan or directly switches the 'high' speed (both fans) as per the CTS criteria.
