My car has a lot of miles and no rebuilds. When i put the new cam in this winter, i cleaned the heads and the manifold, etc. I did everything i could to whatever i had off. That was everything on top of the block. Well my car has a nice little cam, headers, some headwork, and i run like crap. With a tuneup or some piston cleaning/changing would that greatly help me? What else could be going wacky with the engine. When i choke it it runs 100 times better for a minute and then once i put it out of drive once, it goes back to crap. I gotta do something, right?

~Matt

 

From the sounds of what you have, an Edelbrock performer RPM intake, and if you choke it it runs better, what carb do you have? You might want to richen it up a bit, if it's an Edelbrock carb, change the metering rods, and if it's a Holley change the jets. Now if by chance you have TPI on the car, the cam is throwing the computer off and you probably need a chip burned for the ECM. Check out the DIY PROM board if thats the problem. And getting back to your other question about cleaning the pistons, that won't make a difference in your case.

 

If your LG4 is still carbed, and you still have the E4ME, you should check the mixture control solenoid adjustment. Felo is right - from your description it sounds lean. Does it run hot, too?

 

actually, the car stays pretty cold, the most i've seen it reach is maybe 240*. I put in a new 180* thermostat too, but the car runs so much better at like 100*-130*. It's weird. I have the stock Q-jet carb and i was thinking of changing the rods and hangers. That should help. I get real bad bog (carb) but could it be the internals? What could new pistons or roller rockers do if anything? Thanks for your help.

 

by the way, what is E4ME?

 

Time for tuneup?... OF COURSE its Spring!

 

Matt,

You already answered my question in the previous post. You said you have the "stock Q-jet carb", which is a Rochester E4ME, like this:



Item 22 is what you'll be adjusting. If you don't have a manual and need instructions, check back in.

 

it looks like a screw, right? Do i have to tighten, loosen? Does this require me taking parts of the carb off, or can i see it now? Sorry i have so many questions, but thank you.

~Matt

 

oh. by the way. I bought my cam at E-town brand new for $50, and i realized after i put it in that it is for non-egr and i have egr Could this be causing anything? The guy told me he bought it for his 86 t/a but the never put it in. This is actually very frustrating if you can't tell Thanks guys.

~Matt

 

Matt,

If you have the E4ME or E4MC Rochester, you might want to check the TPS voltage. Should be about 0.48VDC at the hot idle position. You should also check the mixture control/enrichment solenoid adjustment. An old dwell meter works well for this, since it is basically a duty-cycle meter. Adjust the control to the low end of the range, and you should be able to call the carburetor good. That's assuming that the float level is correct and the oxygen sensor is functioning.

The ECM requires an accurate reading from the TPS, coolant temperature sensor, and oxygen sensor to adjust the mixture. If the O2 sensor is getting weak, you'll very likely have a rich mixture, not lean, so it may or may not be an issue. You should also make sure the coolant temperature sensor is operating. That can be tested with an ohmmeter as well and compared to the temperature chart: