So I can't seem to find anything directly related to my issue, most surging idle issues that I see are pretty bad.... Mine on the other hand is very slight and slow. I just installed a brand new TPS and adjusted it following 4crawler's guide, it seemed to run really good for a short time. I also for some weird reason do not have a very good cold idle, it hovers just above 1000RPM. Truck runs great otherwise no issues, burning clean, and just passed oregon emissions. I have attached a link to a video of what its doing. OH, and one more thing my power steering pump has a slow drip going into my alternator, which I don't think would have anything to do with it? Appreciate any help, thanks!!

 

Well no answers yet.... Im assuming that might of been a dumb question...... Is my TPS possibly not adjusted properly or IAC? Now sometimes it idles ok, but more often than not it has the slight surge.....

 

Hello 87,

I am having the same issue with my '88. I am having a new TPS put in right now, hopefully it will be right on. My power steering pump is also dripping and I want to know if you found a solution. Did you rebuild it with new seals, tighten hoses?

Thanks, Craig

 

My 3VZE does the same thing now and again, just like in the vid.

 

That idle surge could be a small vacuum leak. Got any old rubber under the hood? They all become suspect after a few decades.

Are you positive what's dripping onto your alternator is atf from the pump?

​​​​​​My pump leak was actually engine oil from 3 different places: the dipstick seal, o-ring on the distributor shaft and dist. hold down bolt.

My mistake was going by location and not checking the fluid on a clean white cloth, or I would've noticed it's reddish color.

After those 3 small repairs my steering pump has proven non-leaky and so the new alternator stays clean.

 

Also, my fast start idle improved a lot after cleaning and readjusting the i.a.c.v. and replaced it's hoses.

It needs to open a certain amount when cold and over the years it gets a little tired.

​​​​

 

No I haven't fixed the problem yet. It doesn't drip all the time its mainly intermittent

 

I have been driving it like this since my first post. Just haven't had the time to mess with it lately. I plan to pull the whole throttle body and go through everything including the IAC valve as it has never been replaced in the 10 years i've owned the truck.

I replaced all of the vacuum lines under the hood, so i'm pretty sure that isn't the culprit.

I will post my results after pulling the throttle body and going through it all. Thanks again guys!

 

I would suspect that the TPS is not adjusted correctly. Adjusting it sound easy, however it is a very very fine adjustment. If the adjustment is off by even a few thousands of an inch there will be issues with idle and other driving characteristics, and timing can not be set correctly either.

 

+1
This is a good point. Just loosening the tps screws will throw it out of adjustment and likewise tightening it back down changes the readings. Go buy a set of alligator clip leads for your multimeter and it'll help cut down on the frustration a lot.

 

When you changed your TPS and may have lost some water from the cooling system while doing the work. You could of got an air pocket in the cooling system. You need to burp the system. I have seen air in the system cause erratic idle.