OK first I need to thank you all for looking and hearing my problem. Second thank u for the help and joining.

OK Now down to my problem.

I have a 85 K30 Chevy welding truck I put a 94 P-Pump intercooled Cummins IN MY SELF about a mouth ago.

MODS include:TST #4 fuel plate
3" straght pipe
4" custom intake
Boost elbow
TST 4K GSK
TORKS 50HP over Flove vlave
Star wheel turned up ( BUT NOT MAXED OUT)
Raptor fuel pump
NV4500 tranny

OK so my problem is ever sence i put this cummins in about a month ago it has had a mind of its own. When i say that i mean at high way speed (60-75 plus But never in the morning) it will randomly give me a dead peadel and rev up or accel. AND I MEAN RANDOM. I dirve 2 PLUS hours every day. somdays nothing happens others its the whole way home. But once again never in the moring. Only after work on my way home.

It only last a few seconds then stops, others it will be non- stop or insted of accel it will kill the pedal all together but wont kill the motor till i hold the clutch. The pump is still rumming tho.

Took it to a shop that i had fath in and they said that their is a rod in the injection pump that gets dirty. kepth the truck for a week and gave me some fuel ativeved and said its fixed. two days later still same problem.


My thoughts: When i did the motor swap i had a shop do the TST fuel plate, 60 LB valve springs and 4K GSK.
I always thought that the 4K springs caused the problem but i didnt know for sure. So one night i took a look at them and tighten them to more clicks. thinking it was going to change the motor a ton. Nothing happened. it strated the same. sounded the same and ran the same. to this day i still think the 4K springs are wrong. I have read that some people keep them loose and others tighten the hell out of them.

All i want is a truck to not give me a deal pedal or die at high way speeds. PLEASE PLEASE HELP> i have called a few places and they said they never heared of this on a 2nd GEN 12 VALVE> so i ask u all to point me in the right direction.

Im all ears.

 

Did you use the ecu from the origanal chevy motor for the 12valve? Or use the ecu that came with the 12valve?

 

does your throttle linkage move freely? you should have waited until you had the motor in your truck and running to do any upgrades that always complicates things in my opinion but I doubt its the gov springs. sounds almost electrical to me

 

So my 85 chevy didnt have one. It was a carb.
The 94 i got came out of a chevy. SO no ECM

I run the SOS to my acc on the key and the raptor fuel pump on a relay on the same set up. that way when i the key is on the truck is on.

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Its got to be something in the P-PUMP. Some say its a plunger in it causing it to get stuck. Any one hear anything like that?


The Linkage is old but free. It dosnt explan how it would cause a dead pedal or cause it to accerate.

 

mine does the same thing, my pump needs to be rebuilt, i run a gallon of two stroke in every tank and it seems to keep the pump happy

 

OMG thank god someone has this same problem. OK now im getting some where. So the shop i took it to for this problem gave me Stanadyne and said i need to run this. Its kind of helping but drove home to day and once again right on Q it acted up. Tomorrow i'm going to call a different shop that rebuilds pumps to get a price or see what they say.

Senotext: do u know what the price is on rebuilding a pump or is it better it just order one from indurstal injection?

Also what about a hardcore fuel addtive or cleaner to clear this crap up.

 

Well im taking mine to northeast diesel service in shelbina mo, they are awesome and fairly close to me, they said about 1200 bucks to start thats rebuilding it completely and maxing it out. there is no cleaner or additive that will fix this, its mechanical wear in the pump, i run a gallon of the supertech two stroke from walmart in every tank of fuel and it seems to keep it a bay for the time being, tried a half gallon once and it acted up

 

Thanks for the info. I looked at some prices at pure diesel power. $1300 with return with a core for $1000 back. That was on a 215 pump which is better then my stock 180.

I called a shop around here and they said the pump was going to be 2K to order one. That seamed a little $$$. They said it sounds like a fuel issue tho and not the pump cause it doesn't stumble and runs smooth. Always starts and only at higher speeds. Like its running out of fuel.

So i have a fuel gauge that i need to install. Ill try and put it in this week end, and next time it does it see what the fuel does. But i only have Sunday off and the truck is going to the brake shop. LOL. Ill keep you all posted.

 

you sure that 215 is better than your 180?

 

I was gonna say something about that too