Problems under acceleration.

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Mar 30, 2008 | 07:36 AM

stangbanger

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Problems under acceleration.

I have searched and found some things trying to get all my ducks in a row here.

I have a 1990 ford f150 4x4 5.0 currently it has long tube headers and i just took the rusted y pipe off so the o2 is inoperable. When i start the truck up sometimes it takes some cranking over then it catches and fires up. <which makes me think the fuel pump is going bad.> And it seems to run ok until i give it gas wether in gear or in nuetral then the popping noise starts out the exhaust at which one point it shot a small flame out one side. Now i havnt been ableto get a pressure guage on the fuel port yet i will be doing that next week when i get off work. I am trying to cover everuy angle and have all the gadgets i need to fix this. The timing is ok, but i feel this is a fuel issue what do you guys think? ALso my check engine light comes on when i hit the gas and it starts popping. thanks in advance everyone and i am sorry if this makes people mad but i did search.

-Randy B

Mar 30, 2008 | 08:12 AM

Powerstroker_18

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From: Monroe City, IN

I'd check fuel pressure, if you have dual tanks switch to other tank and see if it makes a difference

Mar 30, 2008 | 10:05 AM

Conanski

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From: Ottawa, Ontario

You have to put the O2 sensor back into the exhaust system, once the engine warms up the computer is looking for it, if it doesn't see it the motor will run pig rich.. which is likely why you have flames shooting out the exhaust.

Mar 31, 2008 | 12:08 PM

stangbanger

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YEah i got another tank but the fuel pump is bad i have got to replace it. Yes i know the o2 sensor will cause this problem Who ever did the welding on my y pipe before i bought the truck really did a crap job and the flange was rusted right off the pipe and it wasnt making any kind of seal. So i have to either buy a y pipe for longtubes and my truck or get a exhaust shop to build me one. What do you guys recommend?

-Randy

Mar 31, 2008 | 12:25 PM

Conanski

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From: Ottawa, Ontario

I had an exhaust shop make a Y pipe for me a few years ago and it was OK.. not the best workmanship in the world but it got the job done. Last fall I made my own Y pipe from parts and it definitely works better than the previous system, I have a wire feed welder though so this type thing is not a big deal.

I think you may still have some other problem with the engine though, the extended cranking and less than smooth running indicates one or more sensor is out of range. Have you pulled the codes recently?

Mar 31, 2008 | 01:11 PM

quicklook2

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From: Lakewood, Ohio

first read the codes.

second repair the o2 hookup.

then get back and post what happened after you did these things.

Mar 31, 2008 | 06:36 PM

stangbanger

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i pulled the codes before and it came back with egr but i had alot of vacuum issues after redoign the vacuum setup it went away. I will do these things and report back. May be a week or two so standbye!

Thanks!

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Apr 13, 2008 | 12:00 AM

stangbanger

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Well i was going to do a fuel pressure test today but i left the guage i bought in a rental car and its gone DOH! anyways! we did a vacuum check and it held steady at 20.. my father pulled out this trick of holding a dollar bill to the header <truck is open header right now.> And the driver side bank sucked in at times and ripped the bill. And he pulled plug wires one by one and it appears that 2 cylinders are not doing much good on the driver side. He said he assumes this is a valve issue . The truck is not smoking or anythign like there is blow by or ring problems the only thing is the rich running i suppose do to the lack of 02 sensor. Well after a while of running it etc... i noticed the oil pressure guage not feeding a steady streeem of oil and sometime falling to 0. It holds 40 at start and then falls to like 20 and under when hot. So at this point i think the best bet is to go ahead and get everything else i want squared away breaks, roll bar, push bar etc.... And then when uncle sam sends me the check in may i will hunt down a donor motor for this thing.

-Randy