Wammers - I have the flapper model not the one with the idle air valve.

Thanks guys I'll take a look as soon as I get some more gasket! Anyone know what the idle should be for the manual which is what I have?

Looks like a good possibility. Plenum off for the third time! I was just cleaning it! Didn't think I could have f'd something up by just cleaning something but hey ho guess I've got a lot to learn!

Thanks Norseman, I'm thinking along the same lines but I'll give it a try later today and see what happens. It never gets below 15 degrees Celsius where I live so doubt I need the cold start injector anyway. What normal rpm should I be aiming for? It was sitting around 1000 before but as I say...

Thats worth a try but I thought high revs = un metered air entering the system not fuel. What it the purpose of the hose at the rear of the plenum? Is this an air hose? connection seems good but where does it go after the plenum? I'm also wondering if I could have messed up the throttle...

Thanks guys for clarifying that. Been looking all over for that bypass valve! Mine does have the cold start injector. Should I just remove the electrical connection and give that a try? I was thinking that the high revs would be down to air getting into the system, would the cold start...

My idle rpm has started sitting around 1500. Removed and cleaned the Plenum and double checked the seals are good. Checked for air leaks at all hoses and all seem good. Read online that the stepper motor/air bypass valve could also cause this problem but my engine doesn't seem to have one of...

Thanks but will the clutch even engage if there is not enough pressure at the pressure switch located on the drier? I also thought that I should be able to see air bubbles in the sight glass on the drier if the gas was low? I'd like to rule anything else out first as I think it could be pricey...

Ok so after a few months playing around with the A/C and replacing relays etc it's still not blowing cold! As far as I can see everything is working as it should i.e. the compressor clutch is engaging and the fans are blowing but still no cold air. I am assuming (please anyone correct me if...

Thanks for all the info guys. At the moment I'm trying to look for electrical problems with the system as I believe the a/c blower fan should work even if the compressor etc doesn't. I've connected the a/c fan to the heater fan and it works fine. I'm going to replay the relays and see what...

Thanks Rangy 35, I don't really like the idea of messing around with it unless I fully understand what I'm doing. I think she will be on the original R12 gas. There are 2 separate blowers, one for the fresh air and a different one for the a/c. The fresh air blower works but when I switch to a/c...

Datatek, the garages on the island where I live are pretty basic! They may have the testing gear but doubt they have the correct gas for a 25 yr old truck. Think I may be on my own with this one! Will look on Ebay and hopefully get the gas brought to me by a friend some time soon! Oh to live in...

I'm not an electrical expert but can anyone tell me from this wiring diagram if the a/c blower motor should work even if the other a/c components don't? Provided the relay, connections and cables to the motor are ok? I'd be happy to get the a/c blowers alone to work at the mo but I'm only...

Thanks datatek but how do I do that? Do I need to take to a garage or is it something I can check myself?

Hi guys, I'm trying to work out why my a/c doesn't work on my 1988 3.5 EFI. At the moment I have the dash off and have checked the a/c motor works by connecting this to the power connections for the heater motor so all good. Hotwired the compressor clutch and this engages so that looks ok...

Thanks for all the input on this. I managed to repair the vacuum unit (under the dash) that wasn't allowing me to switch between recirculate and fresh air. Taking a meter reading from the heater blower motor I'm getting just under 12v! I would normally have expected a little more with the engine...

So far I have removed the blower fan and this all seems fine and voltage ok, cleaned and lubricated and put back. Whilst I had drained the coolant I needn't have bothered as I managed to get the motor and fan out without removing the whole heater unit as instructed to do in the manual. The...

Thanks Kev Looks like that's the way to go.

Thanks Kev, I have the RAVE file downloaded from this site however I didn't find the instructions particularly easy to follow. For example in the fault diagnostics for this problem there is no mention of checking the hoses to the vacuum unit as mentioned by norseman. I also found the dash...

Hi Norseman, only flap I can see moving under the lower dash is the one that controls whether the air goes to the windscreen or vents etc. The noise I hear is more of a click than a thud so perhaps there is a problem with the vacuum however as the amount of air I'm getting through could barely...