1990 ford f250 starting problems

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Sep 3, 2006 | 10:53 AM

#16

subford

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From: Easton,Ks

Quote:

Originally Posted by brownno

TIMMING is at 10 bftdc fuel prees is good had a mech look at it and he siad the injectors where not fireing when they are sopost to? what evere he means by that.

Could be the pick-up coil in the Distributor.

The 50 psi is too high for an eight at idle, should be in the low 30's psi.
If you check the fuel pressure with it off and pin #6 of DLC grounded then it should be 45 psi. Could be a bad pressure regulator pull the vacuum hose off and see if fuel comes out of the pressure regulator. If it does it is bad.

Sep 6, 2006 | 09:14 AM

#17

MustangGT221

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From: Topsfield, MA

Lows 30s? I thought it was 40-45...but more like 40.

Sep 6, 2006 | 09:35 AM

#18

subford

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From: Easton,Ks

Yes, at idle you have max vacuum that pulls against the Regulator spring and the fuel pressure over comes the spring and the pressure is lower (about 34 PSI). At WOT (or with hose off and plugged) and near zero vacuum the spring will hold the pressure at about 45 PSI on an eight.

And engine at idle may have about 15 inches and 40 PSI.

It all deepens on the amount of vacuum. A six is higher (about 55 PSI) and would have a different FPR rating.

Here is a diagram of the FPR.

http://i54.photobucket.com/albums/g9...Fuel/fpr02.gif

Last edited by subford; Sep 6, 2006 at 09:52 AM.

Sep 6, 2006 | 09:47 AM

#19

brownno

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ok check FPR and it waas bad replaced it but still doing the same thing. is there any way i can check the pick up coil or the tfi?

Sep 6, 2006 | 10:04 AM

#20

subford

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From: Easton,Ks

Quote:

Originally Posted by brownno

ok check FPR and it waas bad replaced it but still doing the same thing. is there any way i can check the pick up coil or the tfi?

If the TFI module did not come from FORD then it may be the problem. The ones that the A/P stores sell are reverse engineered, as FORD has never given out the details as to what is on the inside. So none of them are as good as what FORD sells. Also make sure you put Thermal grease on it. There are a lot of resistance measurements test you can do and they are readily available on the internet but they will not tell you much unless it is at the max temp that you operate it at. The same goes for the pick-up unit as it can open under heat.
Might want to carry an can of Freeze and spray the TFI module when it does its thing and if works again for a while then its the problem.

Sep 8, 2006 | 11:20 AM

#21

brownno

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cool thanksfor the tip just waiting on payday. then i will see what it does.

Sep 8, 2006 | 08:54 PM

#22

mattd95363

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I think your are one tooth off on your timing chain job.

Sep 9, 2006 | 09:28 PM

#23

brownno

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ok pick up coil was replaced TFI also sry but it is a no go still doing the same thing
rechecked the timming chain its good im about to take it to the mech and pay him is dang money