After the engine is up to normal temperature:

I have a situation where the throttle will not always completely close, it stays open enough to keep the engine at about 1500RPM. Sometimes the throttle does completely close and the engine idles perfectly at 750 RPM, I can also reach in and manually close the throttle and it will stay at 750 RPM.

I know that there is a spring to close the throttle, I would assume that this is not the problem because as mentioned above it does go to idle sometimes (without manual intervention). I have completely cleaned and adjusted the throttle plates as per the FSM. Now I need to understand what else can keep the throttle open (thermowax/pellet?) etc., and how to adjust and check these. Does the throttle have to be lubed (with what, where)?

This is driving me nuts, and I'm sure wasting a lot of gas!

Thanks for the read!

 

Sounds like your cold start thermowax is sticking. Should have a good diagram in the FSM (it's kind of hard to explain with text). The cold start cam is the likely suspect.

 

yea man, just take out all the extra **** you dont need. hint: search for TB mod

 

I plan to keep it all stock, so the thermowax, I figured this might be involved, I'll read up on it and it's replacement. Does the thermowax operate the cold start cam?

Aaron, any idea on how much these are in Canada?

Thanks, Al

 

Did you consider thant he might actually like a decent cold idle?

 

why? it will **** up the motor. but it aint my motor, so do whatever u want there guy

 

what do you mean. Why wouldn't you wanna spin your motor at higher RPM's when it's cold, specially when the oil controll pellet is allowing less oil to the rotors so the motor heats up quicker??

My TB would stick at times. turned out cleaning the spring a lubbing it solved the problem.

 

Oh i TOTALLY agree, if I could go back, I don't think I would have removed the thermowax and BAC valve...

In fact, now that im thinking about it, keeping the BAC (I put it back on) and thermowax WITH the coolant lines is the BEST idea seriously for cold starts. Some people say they can start their car without these things in the cold without the foot on the gas, but it sure as hell doesn't work that way with mine. Personally, if im going to get my car to warm up, I sure as hell don't want to balance my foot for 5 minutes..

If I get a new seven, I swear, im only going to be making MINOR modifications. As in take out the air control valve and the egr, the rest is staying. I learned the hardway, but im glad becuase now I understand how valuble some of the stock parts that people call "useless" really are.

 

I think your confused with the cold start selenoid operation that peaks the car at 3000rpm during startup. This particular part is very hard on a cold motor. Keeping the BAC and thermowax is a VERY good idea and only gets the car idleing at like 1500 or so for cold starting. No biggie.

 

oh i freakin agree
even in cold mornings in california... the car will not idle.... if it did, it is rough around 400rpm taht couldnt be that good for the mounts

 

nah im not confused

 

Yes, you are very confused. I should just delete the misinformation you have posted, but several others have already replied to correct you, so I don't see the point.

There's nothing wrong with the 1500 RPM cold idle. It's there to give you a decent idle at a time when the engine is stone cold, and make those initial few miles of driving much easier. It also helps warm the engine a little faster, but then, only marginally so.

The 3K startup is not the greatest idea in the world. Having a stone cold engine fly to 3K immediately after startup just isn't good for it. This can easily be defeated by starting the car in gear, or unplugging the thermo switch on the radiator.

To the original poster, the factory service manual contains a good description of the cold start stuff. Check the FAQ for links. The parts should be easily available from any wrecking yard for a few dollars. Yours just might need cleaning or unsticking.

 

Yeah, you sure are. You have confused two completely seperate systems, not to mention probably confusing the original poster as well. Please don't advise people to "take out all the extra **** you dont need" when you don't even understand these systems yourself.

 

nah im not confused, i know the difference, and I think everyone should take out all the extra **** they dont need.

 

Based on your responses, you seem to be.

And "all the extra **** they dont need" is a matter of opinion. Those systems are in place for a purpose, and they fulfil the purpose very well. I would certainly not want to drive a car in the cold weather that has had the cold start system hacked, and there is ABSOLUTELY NO ADVANTAGE in removing it.

Please do not post misinformation.

 

Aaron, I haven't had much luck with the thermowax, isn't possible to adjust the screw to set the point at which it comes of the cold start cam?

And wouldn't this allieviate the high idle problem as well?

Thanks, Al

 

Well I took a look over lunch time, now I'm not sure but the throttle seems to stay open just a bit, all I have to do to knock down the idle is manually close it completely.

Does this still seem consistent with a bad thermowax?

 

try cleaning it out.

 

Make sure the two adjustment screws controlling the thermowax are set correctly. See the FSM for details. You'll need to pull the TB off to do unfortunately.

 

whats so unfortunate about pulling the tb? it takes like 5 mins

 

I was thinking Turbo. NA's are much easier.

 

Taking off the TB, good for a little fun! Next on the list.

Still seems weird that after the engine is warm, I can reach in and just twist the throttly shaft a little right and the engine settles into a perfect 750 rpm idle?

 

do you have the FSM? if so there is a section that has trouble shooting for idle problems, or throttle problems...maybe you can take a look and see what they suggest to inspect.
but you are on the right track, so keep trying and i'm sure it's a simple problem you will be able to fix easy...

 

OK, I can't belive that no-one, not even Mr. Cake suggested that he check the throttle link tention. The cables from the pedal and the cruise control can cause this problem if they're too tight or in need of a little lubrication.

Warm up your engine, then shut it off and chek/set these two cables per the FSM. Then check their operation and lube if necissary. If that dosn't help, then, and only then, look at the more expensive/time consuming **** to replace. No modifications are ever necissary. (Except maybe grounding, but that's different altogether)