wolverine8490

Just wondering what people thought about this. I have 5 in.-Hg of vacuum at idle. At about 2000 or so rpm, it rasies to about 12 in.-Hg.

If I unhook the vacuum to the egr, and plug it at idle, I get about 10 in.-Hg.

I have tried propane, and carb cleaner to listen for vacuum leaks, and have not come up with anything. Does anyone have any ideas where to look next?

PRO50SC

If I'm reading what you posted correctly, there shouldn't be any vacuum at the egr at idle. That's at least 1 problem. The car must barely idle w/ that little vacuum.

Joel5.0

+ 10" @idle after fixing the EGR problem is still too low....... what cam do you have installed?

wolverine8490

It doesnt idle very well at all. It runs super rich, it burned about 1/2 tank of gas in 30 miles. It has poor throttle response as well. I thought it was fuel/spark related at first, but I guess I have more issues than that.

I read online about checking the intake manifold for leaks, but I mean I have sprayed every inch of this thing down and have found nothing. I know with certain big cams that vacuum readings can be low, but its just a TFS stage 1.

As for the egr, its getting vacuum straight from the intake. I have seen a few things about how the vacuum line is supposed to go into a egr vacuum reggulator, and then out of that to the egr, but I dont have that regulator. The guy who had the car before me must have taken it off.

wolverine8490

I was unaware that the EGR should have no vacuum at idle.. I guess that is what the egr vacuum regulator's job is?

Joel5.0

Leave the EGR off and plug the vacuum line.... the EEC will automatically delete/bypass it in its logic. For a TFS-1.... 10" @ 750 rpms is still too low.

wolverine8490

Will do, any other ideas to why the vacuum may be low? I am thinking about taking it somewhere and having it smoked out for vacuum leaks. You think that is a good idea? I have taken the upper intake off a few times, but have not replaced the gaskets. But I only have maybe 100 miles on the build. \

Also, that is at about 900 rpms idle.

Joel5.0

Don't concentrate too much on the possibility of vacuum leaks, if you checked it + run a DIY KOER self-test, and no lean codes show up...... there is something else causing the problem..... first thing that comes to mind in the list of possibilities is the valve train..... did you check lifter preload?..... having too much will cause the valves not to seat completely and cause low vacuum output + idle problems.

wolverine8490

I have run the KOER tests. I have 2 codes:

34 - EVP
91 - LEAN right side

Maybe the EVP code is becuase of the EGR regulator not being hooked up. 91 is the reason that I check for the vacuum leak. Basically, a buddy of mine said the car was running very rich, and to look to vacuum leaks. I still think it is strange that it runs rich, and the ECM says its lean.

I have not checked the valve train yet. I dont have an adjustable pushrod. I used the pushrods that came with the kit, and if they are wrong, I am going to really get after trick flow. Even though they state inthe instructions to check that. I just really am having a hard time understanding the checking of pushrod length. I have read soooo many articles, and it jus does not make sense. I always did have adjusting rockers though.

86GreenMachine

Dont mean to steal your thread but I have that code to but mines on both sides 41, & 91 .Would it be the oxygen sensors?or maybe even the engine ground ?