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Low Power-Running Out of Ideas, But Not Willing To Give Up!

Old Mar 2, 2009 | 12:27 AM
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Exclamation Low Power-Running Out of Ideas, But Not Willing To Give Up!

I would appreciate some more ideas on a 95 auto with low power. I have owned this pickup for years but haven't noticed how low the towing power has gotten until recently upon installation of a new trans. Thanks for the ideas you guys have already shared on the obvious problems. This is what I have done, tested, observed thus far:
Pressurized intake system
-Found leaking plastic hard line from AFC to head. Fixed with 1/4 " air line.
-Found wastegate diaphragm was ruptured. Plugged both the AFC line and the line running to wastegate.
Boost test
-22psi empty in O/D on a decent hill with accelerator to the floor.
Fuel
-Idle 22 psi / 2000 rpm 34 psi, no load in park
-Vice grip on return line spiked fuel pressure
-New fuel filter and prefilter screen
-Fuel shut-off solenoid adjusted properly
-Accelerator when pushed to the floor does move throttle lever to WOT
Symtoms
-Starts easy
-No major miss or backfire
-No white smoke
-Small amount of black smoke on start up
-Very rarely a small amount of black smoke upon hard acceleration
I am wondering if:
-Timing Slipped?
-Bad Diaphragm in AFC?
-Injectors?
-The boost elbow is located on the AFC, is that a problem since the wastegate is not connected to the AFC anymore?
-Would the star wheel, fuel plate or AFC rattle or move on it's own as they haven't been touched for many years?

So I think that is it. I have read old post after post and can't figure out where to look next. The lack of power is noticable, having to feather the throttle just to get it into lockup on the new trans. Then it is very slow to accelerate. Thanks for taking the time to read all this and maybe throw some more ideas at me.
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Old Mar 2, 2009 | 06:28 AM
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When I first got my 95 I had similar symptoms. The pedal was hard until I built any boost. It turned out that the governor lever was out of adjustment and riding under the nose of the plate.Adjustment was a little tight to get to but not too difficult.Check here for instructions.(http://www.pdrdiesel.com/oldsite/TechLeverAdj.htm)
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Old Mar 2, 2009 | 06:34 AM
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Fuel lines from the tank may have swollen and are restricting fuel flow near WOT.
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Old Mar 2, 2009 | 09:54 AM
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Fuel lines from the tank may have swollen and are restricting fuel flow near WOT.
It sounds like his FP is excellent.

Check/fix the AFC diaphragm. When it goes the engine turns to a dog.
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Old Mar 2, 2009 | 10:53 AM
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From: Northwest, Minnesota USA
Originally Posted by notw
...
-Found leaking plastic hard line from AFC to head. Fixed with 1/4 " air line.
-Found wastegate diaphragm was ruptured. Plugged both the AFC line and the line running to wastegate.
...
-The boost elbow is located on the AFC, is that a problem since the wastegate is not connected to the AFC anymore?
...
I'm lost on these lines.
Is the AFC getting full boost pressure?
If you disabled the wastegate, a boost elbow isn't needed. That only slows the wastegate opening. If you have it in the AFC circuit it will slow/prevent full fueling.
An overflow valve should be replaced periodically.
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Old Mar 2, 2009 | 11:07 PM
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From: Alaska
Originally Posted by Fueling around
I'm lost on these lines.
Is the AFC getting full boost pressure?
If you disabled the wastegate, a boost elbow isn't needed. That only slows the wastegate opening. If you have it in the AFC circuit it will slow/prevent full fueling.
An overflow valve should be replaced periodically.
I am glad that I added that to my list of questions. I just happened to think of it when I was typing all that info. The only leak that I currently have when testing the system is the boost elbow orifice. I will swap out the the boost elbow for the stock fitting. I have a new overflow that just showed up today. The current OFV has over 130K on it.

Totallyrad I am afraid that I already replaced the lines a couple of years ago.

Infidel I would like to take a look at the AFC diaphragm. Is there a link with some info on how to check the diaphragm or just remove the AFC housing and see what it looks like? I did a search but didn't find much.

jdjanetka thanks for the link on governor adjustment. That is another thing that I didn't think of. I also forgot to mention WOT is 2650 by the tach in the dash.

I will start with the boost elbow, overflow valve, gov adj, and then the AFC diaphragm.
Thanks to everyone. I will post back after I have tried your suggestions.
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Old Mar 3, 2009 | 12:26 AM
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From: norman, ok
these years are bad about throttle linkage wear too, recalled on some years? the thing is as they gradually wear you will not notice sudden losses of power. i would have a buddy or a proper sized stick to hold the fuel pedal on the floor and see if the ip is at full throtte. the arm on the ip is known to come loose too and cause like symptoms
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Old Mar 3, 2009 | 10:09 AM
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From: Montana
I would like to take a look at the AFC diaphragm. Is there a link with some info on how to check the diaphragm or just remove the AFC housing and see what it looks like? I did a search but didn't find much.
Mostly good info here but some to ignore since you're only checking the diaphragm, not replacing the spring> http://www.tstproducts.com/pdffiles/AFC-KIT8.pdf
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Old Mar 3, 2009 | 11:07 PM
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From: Alaska
Originally Posted by infidel
Mostly good info here but some to ignore since you're only checking the diaphragm, not replacing the spring> http://www.tstproducts.com/pdffiles/AFC-KIT8.pdf
Thanks Bill, that's what I was looking for. I'll let you know what I find in there.
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Old Mar 4, 2009 | 03:29 PM
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Probably not related to your problem, but as jnicewan brought up the 95's did have a throttle linkage recall. I believe it was #970. I just purchased the kit to do the recall a couple weeks ago from Dodge which included a new throttle cable, ball studs and sockets. It was only like $14 and tightened up the linkage nice.
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Old Mar 4, 2009 | 06:42 PM
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$14 is a heck of deal, they were $38 over ten years ago.
My bet is most rigs have had the recall done by now and there is no demand anymore for the kits.
They just want to get rid of them at this point.
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Old Mar 4, 2009 | 08:41 PM
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Dodge did the throttle cable recall on this pickup in 2000 or about 160K ago. About a week after I received the letter that there was a recall on the throttle cable mine started falling off whenever you would kick the cruise control off. Luckily my dealer had the parts and got if fixed right away.

I have verified that I am getting full throttle while having someone push the accelerator to the floor. Could the linkage still be bad? I would be willing buy and install a new kit if they are only $14. Thats less than 4 gal. of fuel up here.

Now that I think about it. When pressing the accelerator to the floor you can feel a catch at about 3/4 throttle. Does that mean anything or does that sound normal? Also WOT in park is only 2650rpm. Would that indicate a gov. spring problem?

Last night I got rid of the boost elbow and ran the line direct from the head to the back of the AFC cover. I also replaced the OFV, but still no difference in power and maxing about 20 psi boost. Saturday I'm going to check out the AFC diaphragm, governor adjustment and anything else that anyone can think of.

Thanks again for the help.
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Old Mar 5, 2009 | 10:14 AM
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If the engine isn't running you will feel a catch in the pedal.
Check that the two small bolts on the arm on the pump where the linkage connects are both there and tight (holes in fig 9).
Check that the linkage is adjusted as in figure 11
http://dodgeram.info/tsb/recalls/970/repair.htm
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Old Mar 10, 2009 | 01:12 AM
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Got it fixed! I think.

Thanks to everyone for your help. Saturday I spend about 14 hours in the garage and test driving the truck. This is what i found.

-Fuel shut-off solenoid was too short by 3/8". I couldn't tell with it on the motor the 2 times that I checked it. But after removal to get to the AFC I finally got a good measurement.
-The AFC diaphragm was good. Governor adjusted properly, and all throttle linkage was in good order with all bolts tight.
-So I put the AFC housing back on and noticed that it was origionally set about 1/2 way in the slots. I had printed off some info on turning up a P7100. So I thought I would move it full forward and hope for some smoke. But suprisingly none. So I adjusted the star wheel a bit towards the engine. Then some more, and finally a small amount of smoke on take off.

I also went to town and bought a set of permanent guages and installed them, that was the most time consuming. But since I found some new power, I figured I had better keep an eye on it.

So now it runs better than it has in many years. Pulls good off the line and winds up much faster going through the gears. I hope that moving the AFC housing forward is an acceptable thing to do without any adverse side effects? The #11 plate was already set full forward.
Would anyone recommend going to a different plate as a little more power would always be welcome. Also what should I look for with boost and egt #'s?
Thanks again for the ideas on what was wrong. It was great to have a list of things to look for, as I borrow a shop from my brother who lives 60 miles away.
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Old Mar 11, 2009 | 01:33 AM
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Should I be worried about this?

While working on the AFC I found this "bracket" that looks to be broken off at the upper bolt. Anything I should be concerned about?


https://www.dieseltruckresource.com/...0&ppuser=76707

https://www.dieseltruckresource.com/...&ppuser=76707]

Also I noticed on the motor side of the pump there is a 1/8" threaded port that has no plug or fitting. It looks like it has open for a long time. Unfortunately I didn't get any pics. Can I thread in a plug or is it open for a reason?
Thanks
Jerry
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