[casper]

This is what I got from the smog check place. The guy said that I have too much heat in the combustion chamber.

I figured if I use 20W 40 synthetic oil, and flush the old coolant with the new one. It might do the trick. What do you guys think?

Please advise. Thank you.

 

[bobski]

You have an HF, right? I would check if the EGR system is working properly... It's designed to reduce NOx emissions. The valve or one of the tubes might be clogged up with carbon, preventing exhaust recirculation.

 

[casper]

right on... yeah, I have a 1990 HF fuel injected

hmmmm... I am not sure how to go about it. I dont even know what it looks like. I looked at the haynes mannual regarding egr system... it just has a diagram... but suggests to use a vacuum to check the EGR valve. Then it says "....injected vehicles requires special tools and equipment. Take the vehicle to the dealer..." :rolleyes1:

I am going to try to figure it out. Thank you Bobski

 

[tubafreak]

Get a Helms manual (or one of the pdf versions of it online) and use that. the Haynes manual is useful for some things, useless for others. The "special tools and equipment" is most likely a hand-operated vacuum pump ($30 at any auto tool store).

 

[bobski]

If, in that first flowchart check, the valve holds vacuum but the engine doesn't stall, I would unbolt the valve and try cleaning the passages and such. I've never personally messed with an EGR system, so I'm not sure exactly what that involves. I know that the channel from the exhaust manifold is built into the cylinder head - it runs from the exhaust port closest to the distributor over to the intake manifold.

 

[ragtime4]

right on... yeah, I have a 1990 HF fuel injected

hmmmm... I am not sure how to go about it. I dont even know what it looks like. I looked at the haynes mannual regarding egr system... it just has a diagram... but suggests to use a vacuum to check the EGR valve. Then it says "....injected vehicles requires special tools and equipment. Take the vehicle to the dealer..." :rolleyes1:

I am going to try to figure it out. Thank you Bobski

The Haynes manual threw me a bit at first, but note that Hanyes has instructions for checking the EGR valve (vacuum pump) and checking the EGR system as a whole. The EGR system, according to Haynes, requires special tools, but not the valve itself.