engine hard to start, and when it starts, idle fluxciates fo

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mechjames
Posts: 9
Joined: Tue Sep 18, 2007 2:40 pm

engine hard to start, and when it starts, idle fluxciates fo

Post by mechjames »

my 2.9L in my 1989 bronco II is hard to start. usually requiring 3 - 4 turns of the key ( 3 - 4 secs each) before it will start up.

1st turn usually does nothing. 2nd turn, it may start to fire, but will sputter and die. 3rd turn, it will usually start, but stall out after a few seconds. 4th turn it starts up fine.

Once it starts, the idle speed will fluxicate up and down, every 5 seconds or so, then after a minute it steadys out.

i've tried cleaning the IAC valve, and didn't make much difference.

i should also mention that when the truck is warm the engine starts fine.

any ideas?
EBSTEVE
Posts: 291
Joined: Mon Apr 26, 2004 8:10 am

Post by EBSTEVE »

Check the vacuum lines to the air box.
Ranger 5.o, needing another project like Rosie O'Donnell needs another M&M.
mechjames
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Joined: Tue Sep 18, 2007 2:40 pm

Post by mechjames »

there's only one vaccum line to the air box, and its secure at both ends

i've also noticed if i sit and hold the throttle steady while idling, and this is at all times, it'll rev up, and then come down a little bit, then stay steady there.
mechjames
Posts: 9
Joined: Tue Sep 18, 2007 2:40 pm

Post by mechjames »

i found out how to retrieve the codes and will be doing it tomorrow morning
mechjames
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Joined: Tue Sep 18, 2007 2:40 pm

Post by mechjames »

there looks like 2 hookups on the air box and only one has a line attached, is this right?
EBSTEVE
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Joined: Mon Apr 26, 2004 8:10 am

Post by EBSTEVE »

mechjames wrote:there looks like 2 hookups on the air box and only one has a line attached, is this right?

IIRC there should be two, I don't own a BII so I can't tell you for sure but a friends was doing weird idle stuff and the line was the problem.
HTH
Ranger 5.o, needing another project like Rosie O'Donnell needs another M&M.
djadjective
Posts: 38
Joined: Sun Jun 03, 2007 2:45 pm
Location: Omaha, NE

Post by djadjective »

theres two lines coming out of the air box, one hooks up to the intake and is your vacum line while the other is just a drainage line for the air box.
mechjames
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Joined: Tue Sep 18, 2007 2:40 pm

Post by mechjames »

code 13 with engine running

nothing without engine running
mechjames
Posts: 9
Joined: Tue Sep 18, 2007 2:40 pm

Post by mechjames »

i've cleaned the IAC valve out, and when i unplug it while the motor is running, there is no change. When i have it plugged in, it hums a bit. I guess this means the IAC is hooped.
Paul
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Location: Marysville, Indiana
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Post by Paul »

the iac can be cleaned with carb and choke cleaner, but just a reminder the PVC valve can cause the same problem for any who doesnt know.
1989 Bronco II 4x4
Mitsubishi 146 5 speed,
Stock D35
235/75/15
4.0L upgrade
NO LIFT
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mechjames
Posts: 9
Joined: Tue Sep 18, 2007 2:40 pm

Post by mechjames »

nah its not working. pluggin it in and unplugging it and there's no change. the weird thing is, it used to stall out before i cleaned it out when i unplugged it. now it does nothing. Is there a certain way that little rubber oring goes?
ranger5.0
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Post by ranger5.0 »

Sounds like you are lacking fuel pressure.
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420HP and 775Ft lbs Now it is time to break things.
DBrown
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Joined: Mon Apr 19, 2004 5:21 am
Location: Bowling Green, KY

Post by DBrown »

Sounds like you are lacking fuel pressure.
I second that...check pressure at the rail
71 Bronco - twin sticked, full width, 2" lift, wristed arm, lots of rust...

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Paul
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Location: Marysville, Indiana
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Post by Paul »

guys ....... he said it runs fine when the motor is warm, so it is hard to believe it is the fuel regulator......... i would recommend that he pulls the IAC off the truck and take it apart and oil the O-Ring inside ..... when the Oring dries it will bind it usually coated with a vacuum greese ...... but a light oil will do the same thing to tell if thats the problem ....... besides if he cleaned it and didnt re coat it with greese then im positive that can cause the problem .........to me it sounds as the O-Ring is binding ... and make sure you clean it thoroughly with carb and choke cleaner, when your done, grease the O-Ring, that should fix your problem, if it doesnt then you need to make sure it isnt binding inside, take it loose form manifold, key off and use a jumper wires from batery you should visually see it move, do not use the key to try this because it may spray fuel into your eyes.
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Please Be Advised: You Should Always Wear Safety Glasses when working on the fuel system!
1989 Bronco II 4x4
Mitsubishi 146 5 speed,
Stock D35
235/75/15
4.0L upgrade
NO LIFT
Crop Top
mechjames
Posts: 9
Joined: Tue Sep 18, 2007 2:40 pm

Post by mechjames »

yeah, well thanks for your help. the solenoid isn't moving at all. IAC is dead. o ring has been lubricated.

also the truck has a blown headgasket too, so i'm thinking thats why it might be so hard to start, and doesn't run right til its hot. water getting into the cylinders

thanks for your help!
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