By Jaco de Klerk (Jaco) on Friday, November 23, 2001 - 08:42 pm: Edit

Since a recent dyna tune and freeflow fitment, my '94 V8 runs hot. I replaced the thermostat and will have the radiator cored next week. I do however suspect that the fuel mixture is too lean, appearantly this can result in the engin running hot.

The shop that did the tuning is 250km from my home town and I was wondering if I could adjust the fuel mixture myself? How is it done?

By gloverbr on Friday, November 23, 2001 - 10:47 pm: Edit

i beleive this is done via a adjustment screw on the airflow meter.without the use of a emission tester i beleive that if you adjust this screw to a point where idle speed drops then just back so rpm returns to normal.i had my air/fuel mixture done and lowered it from 4 to 1.75 and noticed no change to the temp??.

By Robert Mann (Oldscout) on Saturday, November 24, 2001 - 11:36 am: Edit

There is no mixture adjustment screw!

If you have a lean mixture the causes are bad O2 sensor or low fuel pressure or a bad TPS. The adjustment screw on the throttle body (not the air flow meter) is for base idle speed only , it's not a carburetor!

1.Check your fuel pressure.
2. Check the voltage of the TPS
3. Replace your O2 sensor if it has more than 60k in it.

By Ron L on Saturday, November 24, 2001 - 09:53 pm: Edit

Try the following,

1. TPS Position and voltage
2. Timing may be too advanced
3. Spark plug gap is too short or too tall

After a 30 to 60 minute run at night, pull over in the dark and pop the hood, if the exhaust manifold appears to be glowing it may be either a timing issue or the TPS.

I am not familiar with the early model LR distributor, I do know that most current distributors in other makes have a chip that advances the timing in relevance to the computer-02 sensor readings. If this (if there is one on a LR) is defective you will experience no advance and although it will feel good at the wheel, the 02 sensors will naturally lean the cycle of the engine.

Depending on what was done at the tune may have an effect. Where I am coming from is if the cam was adjusted, whether advanced or retarded more than 1 or 2 degrees also plays a tremendous role in operating temperature.

Another way of knowing if it is definitely a lean problem is pulling one of the plugs. Too clean (white) is a definite sign.

Ron

By Jaco de Klerk (Jaco) on Monday, November 26, 2001 - 02:10 pm: Edit

Thanks guys.. I should have added that as from the same time, I have also experience poor idling. Could there be a common factor here? Up to know I've suspected the IACV but maybe the same problem causes both the poor idling and the hot running? (Or is this wishful thinking..)

Jaco