low idel

[muddinlate86]

any one know what would give me a realy low idel(500 rpm).fixed my vacume leak but still low idel.

 

[BroncoJoe19]

any one know what would give me a realy low idel(500 rpm).fixed my vacume leak but still low idel.

I might have you confused with someone else. Didn't you have timing issues also? I vaguely remember that your mechanic couldn't find your spout connector?

Basically your idle, fuel injection, timing etc are all controlled by your computer. It uses sensors to find out what is going on, and actuators to make adjustments. Since thay are so interelated and interdependant, there are a number of sensors that could come into play, so rather than get a list of possiblities the best thing to do is to pull codes.

Here is a thread that I put together, that I request that you use as instructional for pulling codes.

It really is easy. WIth an '86, the only special tools you will need is a 4 inch piece of wire, and a cheap $8 analog voltmeter.

http://broncozone.com/forums/index.php?s=&...ost&p=74581

Then please let me know what if anything is not clear enough so that I can edit it so that everyone will understand.

Your feed back will be greatly appreciated.

Thanks

joe

 

[muddinlate86]

yeah my earlier prob. was i had a bad dist.i cant get to a code reader right now but i was messing around and pulled the vacume line off the fuel reg.and it ideled better.any htoughts on that ?its running real rich and herd it might be the reg. just want to make sure

 

[BroncoJoe19]

yeah my earlier prob. was i had a bad dist.i cant get to a code reader right now but i was messing around and pulled the vacume line off the fuel reg.and it ideled better.any htoughts on that ?its running real rich and herd it might be the reg. just want to make sure

Thoughts? Yep, by pulling that vacuum hose off, you just caused yourself a vacuum leak.

Vacuum leaks will often cause a fast idle, or a loping idle.

So you had one problem that caused a low idle,

you created a new problem that counteracted what ever caused the low idle,

so now you have two problems. So the truck idles better, but it will cost you more money becuase it is not running properly.

IF your nose was full of stuff.

You could take an antihistamine, which will dry it all out, and you'll breathe better, (oh but they make people drowsy. Ah... you could add a decongestant, (which acts like a stimulant) so that it counteracts the effects of the anithistamine. )So every day you can have your body battleing with two drugs it doesn't need, and you can pay for it every day,

OR... you could blow your nose!

You do NOT need a CODE reader to pull codes.

You need a short piece of wire, and a cheap voltmeter about $8 that you can get at any radio shack, or most autoparts stores.

Running real rich? could also be your IAC, O2 sensor, or MAP sensor.

Your idle could be your IAC valve, TPS, timing, maybe MAP.

You could get twenty replies to your question and eventually each of the above will be mentioned, probably more. So which one will you go with?

I would pull codes and have the computer that tests all of my sensors and actuators tell me what it thinks is wrong.

Your computer knows more about your truck right now than anyone. Ask it... what's wrong?

Then blow your nose.

OK.. off my soap box.

joe

 

[bidibronco]

Hey man, when you pull off that vaccume line make sure you plug it with something. Set your timing with that line off and then reconect it. Make sure your engine is warm. We'll see what we can do with it this weekend. Remind me to get that thing you needed off of my old t-body.

 

[BroncoJoe19]

Hey man, when you pull off that vaccume line make sure you plug it with something. Set your timing with that line off and then reconect it. Make sure your engine is warm. We'll see what we can do with it this weekend. Remind me to get that thing you needed off of my old t-body.

Bidi,

Why would one pull the vacuum hose off of his fuel regulator to adjust his timing?

Either you were thinking vacuum advance, or I am going to learn something here today.

Thanks

joe

 

[bidibronco]

I've always been told that when you time your engine with FI that you need to take that line off for some reason or another. I can't remember at the time though.

 

[BroncoJoe19]

I've always been told that when you time your engine with FI that you need to take that line off for some reason or another. I can't remember at the time though.

I tried googling ignition timing vacuum and fuel regulator and came up with this

<snip>

Fuel Pressure is critical to the operation of a fuel injection system. Always check to insure that you have the proper fuel pressure. On a TBI system the fuel pressure should be a constant 10 - 15 PSI. On an MPFI or TPI system the fuel pressure should be between 30 - 38 PSI at idle with the vacuum hose connected to the fuel pressure regulator. A reading from 38-45 PSI is normal with the vacuum disconnected from the regulator.

<snip>

but nothing more interesting.

 

[BroncoJoe19]

Hey,

Did you guys get that idle fixed this weekend?

What was the problem?

 

[muddinlate86]

no im going to try to just adjust my idle ***** .i have to eplace it any way cause i broke it off.we go the timing set good though my dis.was alittle loose and had to adjust it but still low

 

[muddinlate86]

also when im at a stop im only running off the batt if my lights,heater,etc any thing is on acc wise but when going down the road its fine.alt is good i checked it at advance auto.what do you think? maybe a bigger one? bad ground?

 

[BroncoJoe19]

Did you pull codes to make sure that your IAC, TPS, and MAP are all functioning within specs?

Each of them to one degree or another can affect your idle.

Also... I think that your truck is idleing slow enough that your alternator can't put out enough current.

Pull codes, fix what's wrong, and your alt should be a non-issue. If the alt is still an issue after you have a normal idle speed, then you can troubleshoot it.

 

[muddinlate86]

what do you think would be a good idle speed ?bidibronco is only idleling at around 350 but hes set at that?

 

[BroncoJoe19]

what do you think would be a good idle speed ?bidibronco is only idleling at around 350 but hes set at that?

I am pretty sure that mine is at about 650, maybe a little more.

I have seen other posts that state that is about right.