High RPM Miss

[Eric Kropp]

Just caught up on the discovery of the metal in the distributor. Cool, hope that fixes the miss. I don't really think you should need octane booster or anything like that to get it to pass smog. If the computer and emissions stuff is working it should not detonate or ping at all. Mine has never detonated in almost 20 years. And for 16 of the 20 years it actually ran about 6 or 7 on a 1 to 10 scale. My point is that if the system is working even close it should not ping.....

Eric

 

[TheNicky]

ok so it failed... it barely failed tho... it was running rich...

Ill post numbers a little later dont have them on me...
And i dont know if it was a mistake or not... i went to get HEET to throw in before because i heard good storys... and went to kragen and ended up with seafoam... i did somme in the carb and some in the tank right before smog? thatts what the guys there swore by so i was like whatever... umm on the bright side it passed brake and lamp lol

almost there... i got a free restest so and opinions or help wikk be greatly appreciated...

ill have numbers up soon

 

[Original_Ranger84]

Well I would adjust the mixture screws on the carb. lean up the mix a bit to keep it running good and all.thats the only thing I can think of that allows you to change air/fuel mixtures.

 

[TheNicky]

yea but from what i was thos are for idle only... once the gas is pressed the computer takes over

 

[dangerranger83]

The computer goesn't control how much fuel it gets, it just messes with the exhaust emission controls. We adjust the screws on my dads truck an now hes getting much better milage. Before the adjustments we went on a 45 mile trip and it was using a quarter of a tank. After adjusting we took the same trip and only used a 8th of a tank. His are turn 1.5 turns out but every truck is different.

All I can say is lean the truck out and see what it does. But your almost there one you pass, please let him pass, your golden.

 

[Eric Kropp]

They do tests at two different rpm levels. Did it fail at idle or 2500 rpm? If it failed at idle, run both of the idle/air adjustment screws in together while it is running until it wants to die. Then back them out just enough to make it run smooth, well sort of smooth. The leaner the better for this test. One of the testers told me once that the Rangers seldom fail at the 2500 rpm. Was it hooked up to Sacramento when the test was done?

Eric<><

 

[enginepaul]

I don't know where yours was tested, but in the SanFran Bay Area they are tested at 15 miles per hour and 25mph on the dyno. No idle test, so the idle mixture screws will have no effect. (If you do want to adjust the idle mixture, find how to do a "propane enrichment" adjustment. It may even be on this site somewhere)
The new air filter and oil change helps cut down the hydrocarbons - again a web search should tell you what you need to adjust.
Mine failed the new test early on because two vacuum hoses were switched. It passed the old smog with the same hook-up! so you might want to double check the hoses; I'm sure you already did, but do it again while inspecting them and testing them carefully to be sure.

 

[Original_Ranger84]

and five pages of reasons why I ripped out the computer.... lol Well adjusting the idle screws does control the idle. it lets some fuel get in to keep the truck running at idle with the valves closed but when opened up it still lets fuel in and probably makes the mixture too rich. leaning that out should help alot. I would think I'm not a carb master.

 

[TheNicky]

Sorry for taking so long.. and thanks for checkin back to help me oout...

Heres the numbers

--------HC's-----------CO's-----------NOX
15MPH-143 (max=209)-1.48(max=1.50)-592 (max=1499)
25MPH-142 (max=126)-1.31(max=1.30)-1058(max=1359)

 

[enginepaul]

Almost passed! If you did the oil change, new air cleaner, pcv and filter, clean the hose, had a warmed up engine, I don't know what to do other than a double check of the tune up. Maybe that high speed miss is a grounding plug wire - one with bad insulation or just one bad plug.
A very small vacuum leak may be in there too.
All I can suggest is to re-check everything and if you have cheap wire, buy a set of better ones. Not much help from here, but I still wish you luck on this one.

 

[TheNicky]

I ran a tank of seafoam right before which makes me a little sceptical about it...
I passed at 15mph and failed at 25mph...
yea i can do all that stuff i have 1 free restest...
and i dont think it was warmed up much... they did brake and lamp before smog...
So far i think the miss is gone... it happens every once in awhile but no where near before!

 

[TheNicky]

Was told by a good mech to check vapor can.

CAN ANYONE TELL ME what water or a fluid of sometype would be doing in there...

it was full of it? and what that can do?

 

[85_Ranger4x4]

Was told by a good mech to check vapor can.

CAN ANYONE TELL ME what water or a fluid of sometype would be doing in there...

it was full of it? and what that can do?

Is there a hole in it that would let water in it?

It should be full of charcoal to absorb fuel vapors from the fuel tank until they are released back into the engine. If it isn't getting released back into the engine I suppose it could fill up with gas, but it is hard to mistake gas for water...

I don't know about 2.8's but most vehicles with them don't do anything with them unless they are under a low load condition like cruising on the highway... so it shouldn't be an issue on a dyno.

Get the thing good and warmed up before the next try, usually on computer controlled vehicles the computer doesn't use most of the sensers to run (it runs off of its own program) until the vehicle reaches a certain temperature. They don't run as good/clean when they run off of the default settings.

 

[TheNicky]

Well i know somethings feeding back into my carb... in which i thought was a fuel filter problem so i went through 3 of them... it doesnt smell like gas... it smells like really old water... and it was missing a cap but i didnt think anything of it and replaced the cap?

 

[strvger]

clean it out good, and dry it. maybe coat the inside with some POR-15 or something similar. then go to the wal-mart or some where and buy some charcoal at the pet/fish supplies and refill it then hook it back up. doubt if it will help you pass smog, but you never know.
btw, due to all the problems you're having with smog testing and allthe problems in Ca. in general, that is why my wife and i bought our retirement property in north central Nevada. no smog, no income taxes, very low property taxes, etc. really didn't like Ca. at all when i lived there. good luck to you!!