burntblues

I recently installed a 350 in my 89 RS. Being the pro that I am, I never labeled all of my EGR vacuum lines. I've been driving the car around for a while now, took it all the way to North Carolina, and its had a funny idle to it. I had it diagnosed and the guy says that it had a vacuum leak in it. I checked along the manifold, and that was ok, but I did have to replace the gasket on the TBI unit. The idle still bounces, and I'm assuming that its a leak or a messed up connection with the EGR. I've got a messed up looking EGR, and need the diagram for this specific unit. You can see it at http://www.geocities.com/burntblues/index.html

Any help would greatly be appreciated.

Thanks,
-=-Mike

badbird88

What do you mean by funny idle? If it's an erratic idle where it varies up and down then that is typical of a big cam matched with a TBI computer.

Did you get my e-mail about the EGR routing and the pictures?

TBI engines will have a funny idle if you go from a 305 to a 350 with a higher lift cam than 194 degrees intake @0.05 lift. Without the proper chip and tuning your going to always have an erratic idle (up and down, up and down). How erratic depends on the temp of the car at the time. My car never has idled properly since I installed the 300hp 350 except at certain times when it's good nd warmed up but even then it varies 300 +/- rpms. If you do have the EGR lines routed properly then that Universial EGR valve you have may be causing the problems. You can check for vacumn leaks using propane gas or fuel injection cleaner. I use to use the small, portable bottles of propane and let it flow around all the lines and the TB base. The engine should change to a different tone (speed up or slow down) if the gas does find a vacumn leak. There are only 2 hoses for the EGR valve like I explained in the e-mail I sent you. It may be other vacumn lines. Check the plastic ones for cracks or replace them with rubber vacumn line to be sure.


Do you get any codes? If so what are they?

This may not affect idle but may help overall performance, did you go to a 350 knock sensor and ESC module? Have you put a new O2 sensor in or still using the original sensor? You may need to get a 350 EGR valve also that is similar to the orignal...from a 87+ 350 TBI truck engine. Just make sure the base matches before you buy it...take the old gasket with ou before you buy it.

good luck.

------------------
1988 TA 300+hp 350 w/ TBI and Holley TB unit, Holley projection intake,
WC T-5, 3.42 gears w/ Auburn posi. MSD 6A, edelbrock TES headers, dynomax 3" cat and cat-back system, ACCEL coil, polyurethane bushings all around, aluminum driveshaft, Mr. Gasket open air cleaner.

1993 S-10 w/ 4.3L V6 TBI, slightly bigger cam, Mild polish job and 3 angle valve job on heads, Edlebrock TES headers, Dynomax cat back, MSD 6A, ADS chip

2000 Kawasaki KX 125

[This message has been edited by badbird88 (edited October 05, 2000).]

BK

Did you change the Map Sensor to one for a 350? Mine idles the same way (up and down) because even though mine is a 305, I replaced the heads and cam. If I apply more vacuum to the map sensor, it stops doing it. I have an adjustable Map sensor on order from turbocity, so hopefully that will clear up the problem by tricking the computer.

burntblues

I haven't tried that yet, how does that affect the vacuum system? I don't know much about the MAF sensor or any of the others for that matter...-=-Mike

badbird88

Let me know if that works, I didn't want to pay $80 and the thing not work. Thanks!

BK

I'll know tomorrow-I did order a custom chip before this and the car kept stalling out, I had to put the milder chip back in.