Low on power???
#1
Low on power???
I just picked up a 1994.5 7.3 PSD 4x4 supercab truck. zf 5 speed, 3.55 gears. 240000 miles. It needs a little TLC and cleaning up. I bought it from my friend he has had the truck a couple of years and has maintained it fairly well. It has started to develop a cold skip. It goes away when the engine temp gets up to 130-150 deg. So I know an injector or two are going to be crapping out soon. No major blowby, the oil cap off trick doesnt spit oil out or blow the cap off the filler neck. No blue smoke or white smoke on startup. Revs quickly from idle to 2500 sitting with no load on engine. Straight 3.5" exhaust no cat or muffler.
On to the questions, anyone with similar gearing have trouble pulling small hills in 5th gear at 55-60mph? The truck feels like its pulling a boat but it is completly unloaded. My friend who sold it to me always ran it with the MAP sensor unplugged for more power. I plugged it back up and it is gutless. No power, with the MAP unplugged its better but not like it should be, and there is NO black smoke at all.
So I think the injectors are crap. Or the HPOP is weak. Is there a good way to check these parameters since the truck is an OBD1 setup. I know the OBD II port can be enabled somehow but will it read info from the pcm like the later trucks so I can read ICP and so on?
The truck is up to date on maintenance, it is so slack on power an IDI would outrun it and outpull it. I need some help.
Thank you any suggestions and guidance would be GREATLY appreciated.
On to the questions, anyone with similar gearing have trouble pulling small hills in 5th gear at 55-60mph? The truck feels like its pulling a boat but it is completly unloaded. My friend who sold it to me always ran it with the MAP sensor unplugged for more power. I plugged it back up and it is gutless. No power, with the MAP unplugged its better but not like it should be, and there is NO black smoke at all.
So I think the injectors are crap. Or the HPOP is weak. Is there a good way to check these parameters since the truck is an OBD1 setup. I know the OBD II port can be enabled somehow but will it read info from the pcm like the later trucks so I can read ICP and so on?
The truck is up to date on maintenance, it is so slack on power an IDI would outrun it and outpull it. I need some help.
Thank you any suggestions and guidance would be GREATLY appreciated.
#3
#4
If you unplug the map and it runs better it means your map is bad as it defaults to known factors in the PCM.
Many people route the factory map line over to the hot side of the IC as it increases the boost loss over the intercooler, as it injects additional fuel.
Outside of the map being bad a clogged hose is also common. Pull it off and blow through it.
If you need a map I pulled one from a truck I've been parting. I assume it is in great condition, but I don't know that for a fact.
Many people route the factory map line over to the hot side of the IC as it increases the boost loss over the intercooler, as it injects additional fuel.
Outside of the map being bad a clogged hose is also common. Pull it off and blow through it.
If you need a map I pulled one from a truck I've been parting. I assume it is in great condition, but I don't know that for a fact.
#5
#7
Gotta find a way to read them first. There is no OBD II port under dash just wires hanging where its supposed to be with wirenuts and tape on them. Im gonna have to patch in a port from a junkyard truck I guess. I have read that the OBDI port under hood does not read proper codes I am still researching the subject right now.
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#8
Gotta find a way to read them first. There is no OBD II port under dash just wires hanging where its supposed to be with wirenuts and tape on them. Im gonna have to patch in a port from a junkyard truck I guess. I have read that the OBDI port under hood does not read proper codes I am still researching the subject right now.
#9
No kidding it has been cut, sliced and diced. Its got #6awg house wire run to the tail lights, wire nuts and all. Its a project but she sure runs like a raped ape now.
#11
#12
Lol 14k is so so far to much! No wonder it had all those problems. New filter and oil every oil change!5k miles is about the farthest you want to go on the oil. You can go further,but that is reccomended interval and it is fun for me so I do it every 5k. It is also cheap insurance that you can maybe spot a problem before your motor is destroyed due to lack of inspection/proper maintenance.
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