fuel prblems???

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huffs
Posts: 23
Joined: Fri May 14, 2004 9:33 pm
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fuel prblems???

Post by huffs »

My truck is an 86 bronco2 with a 2.9l 4speed with od. my problem is kinda wierd. If i start up the truck and let it idle it will start with high idle and slow down to normal speed in a few minutes but when i get to a stop sign or light while driving it is back to cold idle again. I am not sure if the other problem is related or not but it might be. whenever i go up a hill and i put the pedal to the floor to make it up at a respectful speed, after the top of the hill and i let off the gas it sputters unless i either let off the gas or hold it about 3/4 of the way down or more. I can smell the gas loading up so i think it is partially flooding itself out while it is running???? but if i don't get the gas to the floor it dosen't do it. any ideas??? oh and the check engine light never comes on but i think it may be burnt out or i need to check the fuses. :hmmm:

PLEASE HELP ME!!!!!
DBrown
Posts: 1545
Joined: Mon Apr 19, 2004 5:21 am
Location: Bowling Green, KY

Post by DBrown »

have you pulled codes yet?
maybe an injector stuck open? or busted fuel pressure regulator shooting fuel back into the intake?
71 Bronco - twin sticked, full width, 2" lift, wristed arm, lots of rust...

http://www.catalystcycles.com
huffs
Posts: 23
Joined: Fri May 14, 2004 9:33 pm
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Post by huffs »

i don't have a code puller yet but i am getting one soon
the fuel regulator seems to be working ok ...i had a pressure gauge hooked up to it for a couple of weeks and it seemed good.
DBrown
Posts: 1545
Joined: Mon Apr 19, 2004 5:21 am
Location: Bowling Green, KY

Post by DBrown »

coolent temp sensor?
try unplugging it and see what happens.
71 Bronco - twin sticked, full width, 2" lift, wristed arm, lots of rust...

http://www.catalystcycles.com
89b24x4project
Posts: 51
Joined: Thu Apr 22, 2004 7:45 pm
Location: pearland texas

Post by 89b24x4project »

i have the idle problem it will jump up in the mornings to about 3000 rpms and idle and i have to press the gas to get it to go back down and then it goes up and down till it finaly idles rigt is that the same problem or is it diffrent how can i fix it
huffs
Posts: 23
Joined: Fri May 14, 2004 9:33 pm
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Post by huffs »

89b24x4project wrote:i have the idle problem it will jump up in the mornings to about 3000 rpms and idle and i have to press the gas to get it to go back down and then it goes up and down till it finaly idles rigt is that the same problem or is it diffrent how can i fix it
no mine wont go down until it sits in idle for awhile then goes back up when i take off again :puke:
huffs
Posts: 23
Joined: Fri May 14, 2004 9:33 pm
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Post by huffs »

these are the codes i pulled with the reader i bought today
key on engine off

11 pass
18 loss of tach input/IDM circuit failure/SPOUT circuit grounded
63 Throttle Position (TP) circuit fault, below minimum voltage
33 EGR valve fault/not closing properly

key on engine on

25 Knock not sensed during Dynamic Response Test

Help!!!!
:wtf:
DBrown
Posts: 1545
Joined: Mon Apr 19, 2004 5:21 am
Location: Bowling Green, KY

Post by DBrown »

ok, you have alot of codes poping up.....so you need to check your harness for any splits in the wiring. if you come up with nothng their....

18 would mean that you mod on the side of your distributer is bad.

you might want to start here. that would control your advance in the timing and could be a part of the problem.

EGR's are notorious for causing problems too.

I would check the wiring and then go for the mod. then check the codes again. if they start to dissapear then you are on the right track. my 2.9L had alot of stuff going bad with it when I got ahold of my 86 and you couldn't really tell it to drive it it just got bad gas milage. so the TP might not be the cause for the idle but it might be costing you more at the pump. my best guess is you have a combanation of alot of problems or you have some wiring problems. yes it could be a ECM problem but I wouldn't lay my money on it. good luck and let us know what you find.
71 Bronco - twin sticked, full width, 2" lift, wristed arm, lots of rust...

http://www.catalystcycles.com
huffs
Posts: 23
Joined: Fri May 14, 2004 9:33 pm
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Post by huffs »

Thanks now i know where to start but it'll be next week beefore i get the chance to take it apart :redneck:
huffs
Posts: 23
Joined: Fri May 14, 2004 9:33 pm
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Post by huffs »

well i started with the easiest one to get at and changed the TPS now the only codes i get are...

Running
25 Knock not sensed during Dynamic Response Test

Not Running
11 pass and

18 loss of tach input/IDM circuit failure/SPOUT circuit grounded

so what wires do i need to check on the module or do i just need to relace it??
I have already replaced the green one to the coil, but with what the code says i don't have a tach fo it to input to...what is an IDM and a SPOUT??
:hmmm:
DBrown
Posts: 1545
Joined: Mon Apr 19, 2004 5:21 am
Location: Bowling Green, KY

Post by DBrown »

they are circuts inside the mod. on the distributer. if codes are dissapearing when you started replaceing then you more then likely don't have a wireing problem. you should look at the 7(I think) wires comming out of the distributer, and just make sure that they aren't messed up or broken. if every thing looks ok then get a new mod and see what happens! you are deffinatly moving in the righ direction!

I might be wrong here because I haven't looked at the 2.9L wiring diagram in about 2 years but I think the knock sensor is wired to the mod. so the next thing I would re place is that. it might make both codes dissapear. that mod. on the side of the distributer is responcable for advancing you timing. so it needs to sence a knock in the bottom to save your pistons from melt down.
71 Bronco - twin sticked, full width, 2" lift, wristed arm, lots of rust...

http://www.catalystcycles.com
huffs
Posts: 23
Joined: Fri May 14, 2004 9:33 pm
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Post by huffs »

i see. so next week is the ign mod
yea :finger:
huffs
Posts: 23
Joined: Fri May 14, 2004 9:33 pm
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Post by huffs »

now that i have driven it...the tps seemed to be causing alot of my problems. the idle is good now and it dosen't load up on fuel when i go up hills along with my tempgauge stays in a consistent spot (at the top of the "M" in norm) so i am putting off the ign mod for another week . Thanks guys you are the best!! :finger:
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