I need help with a stumbling/idle problem

[pantera1683]

Okay, it's been a couple days since I cleaned the IAC valve and so far so good. It's idling normally and no more stumbling. I'm driving to Ft Worth from Houston tomorrow and will keep you guys updated.

[sammy]

to ck the tps use a analogue volt meter needle should have a nice smooth sweep to it . if it jerks then it got a flat spot

[pantera1683]

I just returned from my Ft Worth trip and things went well for the most part. It was smooth sailing both ways until I got back to Houston. I was trying to make it all the way home without having to refuel but the level got down to reserve so I refueled. As soon as I got back on the highway it stumbed. It did a couple more times and then everything was fine for the last 20 minutes to my house. Do you guys think it might be fuel related?

On a side note I stopped by the Amsoil store in Arlington and picked up a few cases of AMO 10w 40

[sammy]

jmho but i dont let my tank get below 1/2 ever . the pumps need the fuel to keep them cool. owning a 20 yr old car there is bound to be tons of trash in the tank . i would definatly change the filter and see how it runs after that . j just remember nothing good can come from running the tank way low . but thats just my old guy way of thinkin .

[sammy]

plus in new braunfels is corey henderson one of the best lt5 guys around . he could figure out what the problem is in nothing flat.

[pantera1683]

Originally Posted by sammy

jmho but i dont let my tank get below 1/2 ever . the pumps need the fuel to keep them cool. owning a 20 yr old car there is bound to be tons of trash in the tank . i would definatly change the filter and see how it runs after that . j just remember nothing good can come from running the tank way low . but thats just my old guy way of thinkin .

I've heard that before, but didn't know at what level is too low. I changed the filter when I first got the car as part of my routine maintenance and the old one looked fine. I think I will pull the pump and take a look see, just to make sure the strainers are clear and have some piece of mind.

I will also pull the IAC again to see if it's still clean.

[pantera1683]

Originally Posted by sammy

plus in new braunfels is corey henderson one of the best lt5 guys around . he could figure out what the problem is in nothing flat.

That's true but I'm not to the point where I need to take it somewhere to get it fixed. One of the reasons I bought an old car is because I like to turn my own wrenches.

[Paul Workman]

Originally Posted by pantera1683

I don't think the vacuum leak is the source of the stumbling either. The secondaries are working fine. I did clean the IAC as it was kind of "sooty" and the idle went back to normal.

I need to get a scanner any recommendations on which one to get and where to get one?

Also, what's the best way to check the TPS?

Thanks

There are several scanners out there; AutoXray, Snap-On, Craftsman, are readily available. Sometimes you'll see a Tech-I (perhaps the most comprehensive scanner) pop up on Ebay. Mine happens to be an AutoXray; the only one I'm familiar with (haven't felt the need for anything "better" or different). I paid around $125 for it and $75 more for the computer software that allow me to graph the results (as opposed to reading the raw data points). Some scanners now come with graphing capability on the scanner itself - which I would opt for if buying another scanner.

But, in the end, I can't remember how many little quirks I've been able to detect that would otherwise frustrate the snot outta me. My first Vette was a 95 LT1 car that would intermittently run crappy. The shop had it and drove it for a week with "no problem found". Harrumph... I bought the AutoXray, hooked it up and took the car for a drive with the scanner in data logging mode. Soon as I hit about 3000 rpm, the right side O2 would short and go to zero volts, indicating super lean. The ECM would react by doubling the injector dwell time, resulting in flooding the right side of the engine (hence the black smoke from one side of the engine). I changed the O2s, and that was that; just the first of several little glitches since on that car and on the Z as well that the scanner has been able to immediately point out. Well worth every penny, dem scanners are!

P.

[sammy]

the thing about corey is you can call him and he will allways try to guide you in the right direction . he is a special guy , just ask rick hipsher , who is in katy tx , he will tell ya about the type of person corey is . you can email him at his business henderson performance any ?you have and he will tell you what he thinks . also rick is very helpfull and knowledgeable as well is his growing band of zr1 buddies . i would change the fuel filter agin just to be safe ,they are cheap and except for the gas mess easy to do . i too love doing my own work but am allways thankfull for the help and knowledge of this forum as i know you are finding out . please allway feel free to pm me if you think i can help you in any way . have a great turkey day