Changing Fuel Pressure Regulator - fixed, broke, fixed again

[JohnG]

guys, I’m changing out a fuel pressure regulator this weekend. I’ve heard I need a special tool. I figure it is safer to ask the experts here than the kid behind the counter at AutoZone.
Thanks in advance

1986 STX, 2.9l

 

[Dirtman]

Only special tool that would/might be needed is a fuel line disconnect tool. I dunno if they used the push on lines that require the tool back in 86 but this is what it looks like. Most auto parts stores have them for like 6 bucks.

You wrap the end on the fuel line, press the tool into the fitting while simultaneously cursing and pulling out and wiggling on the line itself. The cursing part will be necessary on an 86...

 

[Paulos]

Like Dirtman said. I have found that twisting/turning the end of the connector that contains the spring while pushing in on the tool works best. If the connector has been in that position for a while (years) it would be best to twist both ends of the connector a little to break loose the orings that are inside. Try not to use pliers to hold the ends of the connector while twisting (you can damage the part of the connector where the two orings seal). Here's some pictures in case you don't already have them.

 

[Dirtman]

Squirting some lube down into the fitting before attempting to remove it is never a bad idea either.

 

[alwaysFlOoReD]

^^^ +1
I use pressurized brakleen or wd40 in a "pump-n-spray" bottle and an air nozzle to clean out the garter spring from dirt as much as possible.

 

[JohnG]

Thanks so much guys! I don’t know what I would do without y’all’s knowledge.

 

[JohnG]

I thought I would share my fix in the hopes that I could help someone else.

Symptoms: difficulty starting, loping idle, down on power, terrible gas mileage, no (OBD1) codes, terrible shutter at about 43 mph.

I had a lot of red herrings since I was chasing some other bad sensors and vacuum leaks at the same time. I checked many of things suggested by the guys here. One thing they said was check for gas at the FPR. I pulled the top hose and there was a constant drip of gas coming out, about 2 every second. That would explain the bouncing idle. I’m guessing that each drop of gas was increasing rpm and computer fighting the rich mixture.

If there is any interest I thought I might post it as a beginners tutorial. I have lots of photos.

 

[JohnG]

Well after 2 weeks of carefree driving the o-ring connecting the FPR to the fuel rail failed.
Anyone know where to find another? I figured it is best to as y’all than the kid behind the counter

 

[Paulos]

The fuel injector o-rings should be the same size. I get them here,

FKM O-ring 7.52 x 3.53mm Minimum 10 pcs

38mm ID x 41mm OD x 1.5mm CS-Price for 5 pcs

www.oringsandmore.com

I think I tried getting FelPro fuel injector o-rings from Adfavance once, but if I recall correctly they were slightly small. The ones in the link work good for the FPR and injectors.

Oh, and don't use silicone based lubricant on the o-rings in the fuel system. It can clog the injectors.

 

[JohnG]

Well Paulos, I gave the injector o-ring a try and it worked (fingers crossed). I really wish I knew what caused it to fail though.
I did not lube it putting it in originally so I might have damaged it then.

Thanks for the help all.

 

[Dssranger1965]

The fuel injector o-rings should be the same size. I get them here,

FKM O-ring 7.52 x 3.53mm Minimum 10 pcs

38mm ID x 41mm OD x 1.5mm CS-Price for 5 pcs

www.oringsandmore.com

I think I tried getting FelPro fuel injector o-rings from Adfavance once, but if I recall correctly they were slightly small. The ones in the link work good for the FPR and injectors.

Oh, and don't use silicone based lubricant on the o-rings in the fuel system. It can clog the injectors.

What type of lubricant for the FPR O ring do you suggest??