Laine D
Full Access Member
Alright so here's the deal. I am 16 and i am learning all about my sweet little IDI. A couple months ago I acquired an 86' f250 xlt lariat with a 6.9 and a c6. I love my truck, i learned to drive on an 85 and I've been around them my entire life. Last month I went through my fuel system. From the lift pump to the injectors, everything new. Truck has never ran this good. When I put my new IP on I was aware that my VRV was gonna be all outta wack because I took it off to switch it to the new pump. I've been driving the truck for a couple weeks now and it wont shift out of 1st and 2nd unless I'm barely giving it the sauce and I gotta let off for it to shift. I tried to adjust the VRV and I have it racked all the way to point where it should be shifting super early. Still nothing different. BUT, when I am going through a parking lot or something just idling, the truck will shift into 2nd. If I touch the vacuum limes on the IP they make an air leaking noise too, not sure if that has anything to do with it.
So, because it is shifting when I am driving like 10 mph... could my vacuum pump be worn out? not enough vacuum at the proper shifting rpm?
Could there maybe be a vacuum leak or are these systems pressurized? I hate vacuum stuff and I dont know a ton about it
I am going to check the trans modulator to see if fluid comes out
What do you guys think it could be?
Please help, I hate having to let off when i want to shift and hear my U joints decide whether they are going to fly into my back seat or not.
So, because it is shifting when I am driving like 10 mph... could my vacuum pump be worn out? not enough vacuum at the proper shifting rpm?
Could there maybe be a vacuum leak or are these systems pressurized? I hate vacuum stuff and I dont know a ton about it
I am going to check the trans modulator to see if fluid comes out
What do you guys think it could be?
Please help, I hate having to let off when i want to shift and hear my U joints decide whether they are going to fly into my back seat or not.
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