Car stalls at 10psi!!

1chance

Active Member
Joined
Aug 8, 2007
Ok, this maybe long, but Im trying to get new ideas. Rebuilt my engine aprox 3months ago, added a TH350 trans a week ago. 2004R gliding. Anyway car was to much for trans. Now before I took out the 2004R the car ran good, but It (seem) to me by the Scan Master O2 ran low700 on top end, so I made a dual pump setup with a T fitting 2 walboros, hobbs switch on the second one to come in at aprox10psi. After trying the car It would fall on its face at 10psi! O2 go to like 078-050. Thinking the scan master cant read that high, I assumed it way rich! So I disconnected the second pump, and the same thing happends, at around 10psi O2s fall down to 070-050s. I dont think its rich, it backfires:eek: if you press down more. I installed new O2 sensor(heated) Cleaned, and regapped plugs on 28. Also I have a bad eshuast leak. The BLM stays on 142 even driving along, It may go to 139 but back to 142, the only time the BLM go to 128 is on a hard decel. At 10psi the BLM is142-139, TPS 196-176, MAF is at 160-170. Need new I deas in stead of its rich. Had the plugs a while can that be it, coil pack, ign mod. I need to look some where else. My drop the tank to see if the hose blew off one of the pumps. Just need some new ideas.Also It has 20lb of vac at idle.
 
You need to figure out how to log, or atleast watch, your fuel pressure while driving. Sounds like your loosing fuel pressure to me. If you were rich the scanmaster should peg at 8XX and stay there not go down. Where is your exhaust leak at? If its before the turbo fix it. It will play with the 02 readings and the boost.
 
Ok thanks for the reply. I was thinking the Scan Master go up to 999, and then start over 001-002? Anyway I will start with the tank, and work my way forward!
 
Ok, ran another FP gauge to the winshield to veiw FP. After being affaird to go WOT. I lowerd the boost to 16, and floored it FP went to like 60 psi then car began to stumble, and FP dropped to aprox 50psi. So I remove the tank to check my dual pump setup. Well I used one hose that came with the new pump on the secondary pump(looked ok), and used Oreily fuel injection hose for primary pump. The hose for the primary pump was all swollen, and look to be breaking down. I used some new harder line I had to replace that, and then decided to change from the screw style clamps to the other kind that dont chew on the hose(Big Mistake!!) The clamp must not close a tight as the screw type, because now FP never go up, in fact it's going down at the hint of throttle:eek:! So now I got to drop the tank again, and change back to the screw style clamps, hope this solves my problem. Hope this helps someone else, and hope this will fix the problem!
 
Thanks, its killing me that the weather is cool, and I can't go out, and kill some mustangs!
 
I just bought the hanger and billet 2-1 adaptor block from racetronix and was done with it $60 and no headache at all with my dual fuel pumps. Also a "T" is not good for flowing a liquid.

,Dan
 
There is a certain style of hose that is designed to be submersed in the fuel. You should be looking for that hose. Sorry I don't know the name of it. I'll try to look it up and get back to you.



Gates 27097 3/8" Submersible Fuel Hose For In Tank Lines SAE 30R10
 
GOT IT!!! Pull the tank down, and Install the screw clamps. Car is running great, on one pump 16psi street chip. Almost affraid to plug the second pump in.
 
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