OLDS Diesel advice needed 5.7l delta 88

Screwz

Not-quite-so-new-guy
May 10, 2021
28
13
Arkansas
Did you check the fuel for fungus. Diesel can get a fungus if it sits around and plug everything up.you might be clogging up your filter.
 

Oscris

Not-quite-so-new-guy
Thread starter
May 9, 2021
8
3
Did you check the fuel for fungus. Diesel can get a fungus if it sits around and plug everything up.you might be clogging up your filter.
I did, Actually dropped and cleaned the gas tank, blew out all the lines and installed new fuel filters.
 

Turbo Zach

Royal Smart Person
Sep 8, 2015
2,386
113
50130
Step one. Take the fuel line off at the injection pump. Put line in a jug. Turn it over a little bit and see how much fuel you are getting. If you are not getting much fuel? Start taking parts out of equation going back to the tank. Plugged filter? Lift pump bad? Plugged screen some where? Now if you are getting plenty of fuel to injection pump? Then the problem is there forward. Fuel shut-off seliniod bad, or no power to it? Something wrong with injection pump? If you have fuel to the injection pump, then take the injection lines loose at the injectors and see if it is getting fuel there. Also if you have a loose or cracked hose or line before the lift pump? It can suck air instead of fuel and cause the problem you are describing. Hope I make sense? I do this stuff for a living, but it is hard to explain in text. Good luck!
 
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Texas82GP

Just-a-worm
Supporting Member
Apr 3, 2015
7,054
113
Spring, Texas
Step one. Take the fuel line off at the injection pump. Put line in a jug. Turn it over a little bit and see how much fuel you are getting. If you are not getting much fuel? Start taking parts out of equation going back to the tank. Plugged filter? Lift pump bad? Plugged screen some where? Now if you are getting plenty of fuel to injection pump? Then the problem is there forward. Fuel shut-off seliniod bad, or no power to it? Something wrong with injection pump? If you have fuel to the injection pump, then take the injection lines loose at the injectors and see if it is getting fuel there. Also if you have a loose or cracked hose or line before the lift pump? It can suck air instead of fuel and cause the problem you are describing. Hope I make sense? I do this stuff for a living, but it is hard to explain in text. Good luck!
Glad to see a Diesel Tech. weigh in.
 
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84dragcutlass

Royal Smart Person
Supporting Member
Aug 20, 2009
1,074
113
North Vernon IN
I agree with turbo Zach, could be something wrong with the injection pump. Or the injectors aren't popping like they are supposed to. If you Crack the lines open off the injectors you should get a spirt when you spin it over. I find it's better to work your way back from that point. Also there is a fuel shut off on the injection pump that has to be getting 12 volts or the pump won't fire fuel, so that's a big one for a no run situation. If it ran then stopped that might be something to look at
 
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Oscris

Not-quite-so-new-guy
Thread starter
May 9, 2021
8
3
So update on the car, it runs!!! You guys nailed it with the injection pump. Ended up pulling it and having it cleaned and rebuilt. She starts and runs like a champ now. The diesel shop told me the metering valve was stuck in place and wasn't moving. Now that it runs I have another issue. At about 45 to 50 mph it dosnt seem to want to shift. Any ideas on this?
 
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Oct 14, 2008
7,471
113
Melville,Saskatchewan
What trans is in it?
 

ELCAM

Greasemonkey
Jun 19, 2021
163
43
It makes the 1-2 shift but not the 2-3 shift?

Sounds like the car is original so it would have a TH350. Three things I would check.

Check the vacuum line and modulator valve. Back of transmission on passenger side has a vacuum line going into it. Steel line with rubber hoses on the ends. Check the rubber ends for leaks see if it is rubbing anywhere that could put a leak into it. Pull the valve and test with vacuum. Apply vacuum and see if the plunger pulls back.

This valve moves a steel valve in the transmission valve body. Use a magnet to remove the valve. If it comes out real easy it is ok, if you have to put the magnet and pull on it over and over to get it free it might be gunked up and getting stuck. If it is getting stuck clean with a scotch brite pad or plastic brush do not use sandpaper or wire brushes. Make sure to put it back the same way it came out.

Check the governor. Cover on drivers side of transmission toward the back with wire clip holding it on. clean oil passage and make sure the weights are free. Inspect the plastic gear for damaged or missing teeth.

Kick down cable. Drivers side front just above oil pan goes to throttle linkage. Male sure it is free and moves easily and adjusted properly.
 

Oscris

Not-quite-so-new-guy
Thread starter
May 9, 2021
8
3
Thank you for that Info Elcam. The car is all original, 50k miles, so you are probably correct that it is a TH350 transmission, but I don't know how to verify that. I can get the car up to about 45mph, but thats where it tops out. If I try to continue accelerating the engine overspeeds and the governor kicks in. I will start checking the items you have listed and let you know what I find over the next few days as I get time to work on it. I really appreciate all the knowledge and advice everyone has and offers here.
 

ELCAM

Greasemonkey
Jun 19, 2021
163
43
I don't think what I posted earlier is valid. With the new info you gave it sounds like something else. Perhaps the 3rd gear clutch slipping or the torque converter. How long did this sit without being ran?

On the passenger side of the transmission there is a round aluminum plug about 2-3" in diameter toward the back behind the big aluminum plug there is a pipe plug that is the line pressure test port, just in front of the big aluminum plug at about 2 o'clock seeing the big aluminum plug as an analog clock is another pipe plug it is the 2nd gear test port. toward the front in front of the dipstick tube is a third pipe plug it is the third gear test port.

You need a 300PSI or better pressure gauge to test these.

Line is always under pressure to some degree.
2nd is under pressure when the 2nd gear clutch is applied.
3rd is under pressure when the 3rd gear clutch is applied.

If you can hook up the gauge and bring it in the car where you can see it, with your foot in it and trying to accelerate it should be over 200 PSI once it settles in third gear (takes a second because there are accumulators that soften the shifts, that's what's under that big aluminum plug the 3rd gear accumulator).
 
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