I bought it a few days ago and had to tow it home. It starts and sounds pretty good-- when its cold it idles at an estimated 1100 rpm for about five minutes, then it slows down to about 8-900 rpm for about five more minutes. Then as the engine becomes warm it idles down a little more and dies altogether, and you can't give it any throttle or it dies even more seriously. So what's making this thing so touchy about the throttle? Is there some device that allows an idle when its cold but malfunctions as the temp increases?

I am determined to get it running in my driveway. If I fail completely I will have to tow it to a real mechanic.

Here's what I'm doing tomorrow: draining the gas tank, changing the fuel filter. Since it sounds so good (at first, when it's cold) I'm assuming the plugs and wires are okay for now. I don't see any obvious vacuum leaks.

Could there be a plugged jet inside the carb that allows it to run on a fast idle mode, but fails when running on a plugged main jet?? As you can see I'm no carb expert.

Any suggestions will be welcome

Well most are gonna ask for more details so I'll list a few so the more exp guys have them.
How many miles?
What kind of carb?
What ignition system?
If it's lean burn then there's plenty on here to help convert to GM HEI like I did.
Compression check? If so what's the numbers?
Is it even a slant six?
An and all details of the motor: rebuilt, cam, timing etc.

These are just some questions. It's not imperative that you know all go them but if we are going in a treasure hunt then we will need clues it is probly something simple and with the exp here along w some time, you will have it running AND driving.

For now it makes me think 1) fuel flow is screwy. Like enough for idle circuits but not any more. Or 2), rings. Cold it seals better and as it warms and metal expands then the seal of the rings fades. I'd lean more on fuel issues.

More exp guys will be by soon, even some that live up in wa. I got a friend out in port Angeles. Get some details and we can go from there but don't give up on it. I've been told for weeks that I can't turbo a slant, it runs well at 8# of boost

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225, Offenhauser, Holley 350, A833OD, 3:55, GM HEI,99 Durango starter
BOOSTED! WH1C, BIG FMIC, 10#
Operation Noble Eagle 03-05
Operation Iraqi Freedom 05-07
Operation Enduring Freedom 12- 13

More clues: it's a 225 I-6, has a single barrel carb, don't know more about the carb but it is all original, its a low miler, (91,000 miles) one-owner truck bought new by an old guy who let it sit outdoors after he lost his license to drive. It sat for at least ten years til he died and then his family sold it . All the smog stuff is intact, the plug wires appear to be originals. It's dusty but unharmed other than that.

I put in a new battery and cables and it starts right up and runs nice, but as it gets warmer it idles lower as it gains temperature, and after it reaches normal operating temp it just dies and I can't get it to idle at all, and it won't allow any throttle at all. I think it will be a simple problem that is eluding me. I am a capable amateur, I have a good selection of tools and some experience as a shade tree mechanic, but this has me stumped.
I looked in the dist cap and it looks okay--it has an ordinary looking rotor and the shaft seems to have little play. I don't think its an electronic ignition. I will be glad to upgrade to an electronic ignition like Pertronics or something like that, but I want to get it to drive without taking it to a professional mechanic. Maybe I will have to, but I am still trying to solve this mystery myself if possible.

Here's one thing I notice: everything under the hood is dusty as can be, but the carb is way cleaner than anything else. I wonder if someone has done any carburetor work on it? There was no evidence of any other work under the hood. no other clean spots. Now that I have been under there its obvious I have been there with the new cables, etc. Maybe its just a super clean carb from the 80's? Just an observation.

A 1986 truck has electronic ignition (All Chrysler vehicles had electronic ignition after 1973), the question is whether it is the oldr "standard" electronic ignition or if it is a "lean burn" ignition system. Beginning in the mid 70s, Chrysler used a series of increasingly complex computer controlled carburetion and ignition systems. These systems were problem prone when new and are very expensive and somewhat difficult to maintain now.

The lean burn systems came in three variations- computer controlled carburetor only, computer controlled ignition only, and computer controlled carburetor and ignition. By 1986 it is very likely that your truck was built with a computer controlled carburetor and ignition system.

If you plan on trying to keep it stock and repair what you have, it is imperative that you get a factory service manual for your specific year of truck. It will have all the troubleshooting and repair instructions you need to get the lean-burn system working.

Of the top of my head, the most basic and important things you need to verify on a lean burn system are; (1) that the coolant temperature sensor (this is different from the sensor for the dash gauge/light) is working and properly connected to the computer; (2) that the vacuum transducer on the computer still holds a vacuum; and (3) that the vacuum transducer is connected to a source of constant manifold vacuum (full vacuum at idle with the throttle closed). It is also important to verify that the base timing is correct.

It may be a slant six powered truck, but by 1986 the lean burn systems were getting complex enough that you must get a factory service manual and not rely on shadetree mechanic advice.

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Casually looking for a Clifford hyperpak intake for cheap.

The computer is located behind the battery under the fender, it controls the vacuum advance, and few other things.
You still have to set the base timing, I think it's 12 degrees.
Idle setting will be listed on the emissions sticker under the hood along with what base timing should be.
If you want to do HEI conversion i have writeup they may help you. http://1drv.ms/1DSutGA
Verify the choke is opening all the way as it warms up(sounds like it is).
Can you accelerate the engine while its on fast idle or does it die?
If not the accelerator pump may not be working.
As far as idle goes could be dirty idle circuit.
It may not hurt to rebuild the carb.
Awhile back my truck all of a sudden would not idle, did everything else fine.
So i pulled the idle mixture screw out and sprayed carb cleaner in there.
If you try that turn the idle mixture screw in all the way till it seats counting number of turns. DO NOT CRANK DOWN ON THE IDLE MIXTURE SCREW WHEN YOU SCREW IT IN!!!
IT IS TAPERED ON THE END IF TIGHTEN IT TO TIGHT YOU WILL RUIN IT.
It should just barely touch the seat.
Then when done cleaning screw it all the way in again GENTLY SEAT IT and then back it out that number turns it was before.

Dave

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86 Miser 170,000+
2 1/4" exhaust
Holley 1920 #55
HEI MSD BLaster 2
17.8 mpg

Idle may also be as simple as the idle speed slow set too low. However, your carb may have a idle stop solenoid on it. Idle stop solenoids are good to have, but the proper procedure to set the curb idle must be followed. Again, this is where a factory service manual comes in handy.

Converting to HEI on a lean burn vehicle is actually very very easy. If you decide to go that route I can tell you how to do it.

The last lean burn engine I played with was a 1986(?) 318 in a Chrysler Fifth Avenue. Its base timing was 16 BTDC. Your base timing will be on the green and white emissions sticker on your inner fender or hood bottom or radiator support panel.

Personally, I would be looking at carburetor adjustments (a full rebuild or at least adjustment is a good idea), vacuum leaks, and mis- or disconnected lean burn components. Lots of people in the 80s and 90s didn't have a clue about how lean burn systems worked and disconnected or removed components with no knowledge of what they were doing. Plus, the vacuum hoses on lean burn systems are a nightmare but must be hooked up properly for it all to work. Again, your best bet is to get a factory service manual and start by verifying everything is connected properly and adjusted properly.

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Casually looking for a Clifford hyperpak intake for cheap.

Are there electric wires going to the carburetor?

Could the EGR valve be opening at idle as the thermal thingamagigey in the front of the head that the EGR valve is connected to warms up and allows EGR function?

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Tom
'86 Alfa Romeo Spider, red "Dinsdale"
'10 Corvette, red "" (no name yet)
'95 Ferrari 348, red "Zoom"
'04 Maserati, black "Evil"
'05 Aston Martin DB9, green "Bond, Treasury bond."
'82 Dodge W150 Power Ram, yellow "E. Valdez"

Here are some more clues: There are small "boxes" in the rear of the firewall area on the left side as you look under the hood from the front (passenger side). I have no idea what these do, but there are five small vacuum tubes running to the center of the engine bay, turning along the valve cover. Halfway down the valve cover they ALL turn toward the carb. then they are all broken, all are open.
After removing the air cleaner I can see the ends of the tubes where they are plugged into the carb, (at least three of them) I plugged them up thinking I was fixing a vacuum leak.
I don't necessarily need to make it a restored truck--I just want it to run simply and reliably.
Maybe I should replace all the vacuum tubes and try it? Maybe it would run just fine?
I appreciate the responses, it lets me know what YOU know. Its clear there are some emission items that I can't just figure out based on my previous experience.

It couldn't be too hard to replace the vacuum lines and try it, no?

There is a vacuum diagram under the front lip of the hood. It's readable, but I don't understand it yet. Still working on it.

Oy. Best things you could do to help us help you is to get some good resolution, somewhat medium sized pictures of the engine bay showing the tubes and the wires that are around the carb and the distributor, and a picture or two of the computer (as has been mentioned it is most likely under/behind the battery).

The cubes on the firewall are likely the EGR timer, voltage regulator, and some other emissions timer or device. Pictures will help us ID them.

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Casually looking for a Clifford hyperpak intake for cheap.

Factory service manual can be had from Bishko books http://www.autobooksbishko.com/search.c ... hop+Manual
They also have a store on ebay where you can sometimes get them cheaper.

Dave

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86 Miser 170,000+
2 1/4" exhaust
Holley 1920 #55
HEI MSD BLaster 2
17.8 mpg

$42 on eBay HERE That's a good deal.

If you don't mind having it on CD, here it is for $26 on eBay- click here That is another good deal.

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Casually looking for a Clifford hyperpak intake for cheap.

Click on the pictures, they get bigger. Actually, right cick or control-click and open the image in a new tab. Then you can download or print them bigger.

Lean burn component locations (this is for an air cleaner mounted computer. Everything is the same on your truck except the computer is by the battery, s the ten and twelve way connectors are over there):



Carburetor vacuum line hookups (ESA tube is the hose that goes to the lean burn computer):



Carburetor adjustments:









The following wiring diagrams have the entire lean-burn system highlighted in orange. You will see that it is actually a separate harness that can be fully removed by cutting only a few wires at factory splices. I wrote in blue pen which wires to cut and where.

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Casually looking for a Clifford hyperpak intake for cheap.

Directions on how to troubleshoot and maintain a lean-burn system (if you are crazy enough to try). Again, click on the pictures and they get bigger:































This should all help you troubleshoot a bit better. Go slow, be patient, trace every wire and hose to make sure they go where they are supposed to, make absolutely 100% sur the vacuum transducer on the lean burn computer (a) hold a vacuum and (b) is getting a MANIFOLD vacum signal.

Let me know if you need more help.

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Casually looking for a Clifford hyperpak intake for cheap.

Photobucket is acting weird. Right-click or control-click the imag and open it in a new tab. It will open up bigger. You can download them or print them.

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Casually looking for a Clifford hyperpak intake for cheap.

With the truck having sat for an extended time, I would expect gum/varnish in the bowl of the carb possibly plugging the main jets and/or the intake for the accelerator pumpfilling the bowl with carb cleaner and letting it sit overnight may help the off idle performance. jmo

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Dave

1977 d-200 crew cab ex-army pickup wants it's /6 back
1962 Valiant 2 door, 170, three on the tree
1972 d-100 parts truck
80 volare wagon now a parts car