Issues after Perrin Fuel Rail Install

[magnumP5]

Just to keep this updated for future reference in case someone else has problems.

So Saturday morning rolls by and I've got to run to the PO real quick to mail something off. Everything seems just perfect with the exception the CEL is still on. Well sitting at a stoplight all is fine when I notice the AFR creeping up lean again to roughly 16:1 where it stays for about a second or two before returning to normal. No hiccup or anything, just a random lean spot. So I got to the PO parking lot and let it idle for a little bit and it did it one more time, same deal. I don't get it - the idle was fine for two days and now it was acting up. Well I go to an Advance Auto and sure enough it's P0171. Had the code cleared and drove along on my merry (not so much) way. Anyway, everything seemed fine after that. No lean idles or anything. Afterwards I decided to clean the air filter because it had been a while and maybe a dirty air filter was causing something (grasping at this point). Well reinstalled a clean(er) air filter and started her up to take for a drive. After fully warmed up I immediately noticed a slightly smoother idle. That was yesterday and I've driven about 50 miles since and the idle is still smoother and no lean spots as of yet. Guess I need to gie it a few more days to see if another CEL will pop up.

Oh yeah, I also tweaked some values in my AFC to see if I could make some out-of-boost AFRs slightly richer. Didn't seem to have any effect (AFC takes over at 1 psi anyway, but I was told it works slightly all over) but then again the idle is more stable now.

 

[magnumP5]

Update:

Well, I definitely have a fuel leak...

It's not big - in fact I wouldn't have even found it if I wasn't looking. It appears as the connection of the braided steel hose with the fuel rail isn't all that great as I had expected. After driving the car to and from work today I was checking around that area. When I pulled my hand back I noticed the faint glistening and aroma of gasoline. So naturally I got a paper towel and stuffed it down into the area and pulling it out after a few seconds yielded what I had feared. It's just a small leak - nothing spraying or anything but it's enough to accumulate some gas around the fitting.

Could something this small really cause idle issues? Granted, no CELs since Saturday but the idle can be a little weird at times.

 

[darkane23]

Hmmmm, that's weird. I don't think a leak that small would effect it enough to throw a CEL but it might be enough to cause a rough idle. At idle I guess it expects X amount of fuel and just a few drops of lost fuel can make a difference. As a temporary fix you could try to continue to make the idle richer and see if it will stabilize. Also can you switch to a rubber hose to try and stop the leak just to test? The new filter might have had something to do with it too. The old dirty filter might have allowed the MAF sensor to get dirty, idk. Maybe you could try cleaning that as well.

 

[magnumP5]

^^^ I've already richened up the idle a little but I might try bump it a little richer still. Unfortunately I can't just swap out the braided line - the two ends are held on by some pretty beefy clamps. Either way, it's not leak from the line at all - it's leaking from the connection of the line and the fuel rail (the braided line is clamped to a 3/8 NPT fitting and fuel is somehow leaking around that fitting). It's only enough fuel to leave a little line of moisture around the connection and my fuel pressures are still within acceptable limits (barely - peak 40 psi and after 5 minutes it's down to 30 psi; FSM requires a peak of 39-45 psi and it must hold more than 22 psi for at least 5 minutes). My first goal is to remove that fitting from the fuel rail and wrap it with some teflon. It may not solve the problem but at least I'll know nothing is leaking from that point anymore.

 

[Maxx Mazda]

Ya, it's leaking a LOT more than you think, the problem is is that gasoline evaporates really easily, espesially when there's alot of heat involved. It's leaking out and evaporating right away. Run your fuel pump for 10 mins, car cold and observe.

 

[ForceFed]

And DOn't use TEflon on Fuel lines....
Thats a No-No.

Permatex 59235 will work for you.
AutoZone Or Advance should have it or can get it.
Technical Info HERE

 

[magnumP5]

And DOn't use TEflon on Fuel lines....
Thats a No-No.

Permatex 59235 will work for you.
AutoZone Or Advance should have it or can get it.
Technical Info HERE

Why is that? I was told teflon would be perfectly fine. I currently have my fuel pressure gauge and fitting wrapped in teflon and everything is fine over there. Will gasoline eat through the teflon eventually?

And yeah, I've assumed the leak is actually bigger than I've seen. It's so hard to tell because the gasoline evaporates so quickly. The first few times I had fuel on my hand it evaporated so quickly I thought I was seeing things. The car has been sitting in the garage all day (took the truck today) so I'm going to go over the fuel system again when I get home from work. I need to check out that Permatex stuff...

 

[Maxx Mazda]

Teflon in a fuel system is a no-no. Permatex is good stuff.

 

[magnumP5]

Well so much for getting anything done as it looks like I'm going to have to order this ; none of the local shops have it in stock. And I really wanted to fix this fuel rail and install my new gauges this weekend... I still have to solve the problem of getting that fitting off however.

EDIT: Oh yeah, thanks a lot Mr. Advance Auto Guy who told me teflon would be fine!

 

[magnumP5]

Well I went to Advance Auto and got the Permatex High Temperature Thread Sealant (they only had the 6 mL tube) so I wasn't completely SOL. Got home and immediately set to ripping apart the fuel system (I'm getting good at this now) and had everything apart except that braided steel line within 15 minutes. Now that braided steel line connection was a major PITA. There was nothing I could do to break it loose and I had to go to two shops before one of them could break it loose for me. I really don't know what Perrin used to seal the connection but it almost looked like the anti-seize stuff you put on spake plugs but it definitely wasn't. I also talked with a guy who is very knowledgeable with lines and he informed me the Perrin uses a teflon line which is not good with crimped ends (which the Perrin is). So he was thinking it was probably leaking at that connection and not the fitting considering how tight it was. I don't really have too many options right now so I just decided to reseal the fitting and see what happens. If it's still leaking at least I'll finally know it's coming from the crimp connection and that's final. Now I just have to wait and hope this sealant stuff is as good as everyone says it is. I also used it on all my other connections I'll be using for my gauge install this weekend. I won't be starting the car until probably Sunday afternoon to give the stuff time to cure.

 

[808MP5]

subbed....

 

[mspeedP5]

Subbin' and noting the lack of attention from EMPIRE...

 

[magnumP5]

Subbin' and noting the lack of attention from EMPIRE...

Eh, not really his fault. I wish I could inspect one a fuel rail from Perrin from before this group buy; like when they still made them regularly. This way I could check the quality and type of line used.

So anyway, I decided to go with the Permatex stuff. It's pretty crazy how that stuff spreads through all the threads. However, even though I doubled up on it in most places that stuff still isn't dry but it looks like it's creating a decent seal. The P5 is in several pieces right now because I've decided to install just about every part I've had lying around. I'm waiting on an AWR oil pan and some exhaust mani studs and I'll have everything I need to put her back together. I've decided if I'm still getting a leak at that connection it has to be because of the braided steel line and I'll be swapping it out for a regular high-pressure fuel line. Won't look as nice but at least I'll have the peace of mind a fire won't start in my engine bay!

Hopefully this Permatex stuff does it's job because I've replaced just about every bt of teflon tape with it. It'll probably have another week to cure so I guess that's good. I'll have more updates when the car is actually running again.

 

[mspeedP5]

I still haven't installed mine and now I'm thinking I should re-do the seal before I even start... *doh!*

 

[magnumP5]

I still haven't installed mine and now I'm thinking I should re-do the seal before I even start... *doh!*

I would just for safety's sake. Be warned however, the fitting with the braided steel line was an absolute b**** to get off! Even with a flare nut wrech I couldn't get it off. I was finally able to remove it buy putting it in a vice and using a much beefier flare nut wrench. The other side isn't as bad - you just need the right allen key. Just either wrap it in teflon or use a liquid teflon like Permatex. I have heard it from good authority that teflon is fine on fuel fittings, just make sure you don't wrap the first few threads (common sense, right?).