Need a little troubleshooting help...

[macg33k]

I just recently (and very abruptly) began having problems with my XR and am hoping to get some troubleshooting suggestions.

A little background:
Ever since I installed the URD fuel pump kit (Walbro 255), the engine takes a little longer to start (if it's been sitting a while) and sometimes I get a couple of CELs - evap codes according to my Scanguage.

But just last week, I've started having a sudden and extreme loss of power under acceleration. If I keep light on the throttle, it's not so much of an issue, but if I give it any more than 1/4 throttle, it starts to hesitate and surge badly, and if I continue to give it more throttle, it goes into protection mode and loses all power until I let off. I don't have a proper A/F gauge, but I've been watching the AF gauge on my Scanguage and when it starts losing power, the numbers jump all over the place, but tends to be mostly lean (15-16). And it is not reporting any CELs when this happens.

Here are my relevant mods:
TRD Supercharger
URD 2.825 pulley
URD fuel pump upgrade
URD Y-pipe
TRD intake

So far, I've cleaned the MAF, and that didn't seem to help. Also, it may be worth mentioning: the truck doesn't get driven much. Only about 28K miles on it total (it's a 2007).

Any suggestions where to start looking to solve this problem?

Jeff

 

[x-runner kid]

Sounds like a fueling issue to me. Like maybe a pinched line when you did the upgrade. Do you have a fuel pressure gauge?

 

[NHXRUNNER]

Does it happen all the time or just below a certain fuel level? It's most likely an installation issue with the pump. I could see how the high pressure line could get kinked in the installation process. I've also heard of that happening causing a small break in the line and the symptoms only show up when the fuel level falls below the cut.

 

[NHXRUNNER]

If you have to repair that line be sure that it's a line rated for fuel submersion.

 

[macg33k]

Thanks for the replies. I've been thinking it seems like a fueling issue, too. I don't have a fuel pressure gauge.

An installation with the pump seems possible, although I really tried to be careful and follow URD's instructions. My only hesitation with that idea is that I installed the new pump about 5-10K miles ago, so I would have figured I would have seen the issue before now. But maybe my slow crank and evap codes are hints at this being the issue.

The issue seems to happen all of the time, although maybe not quite as bad when the tank is full. I just filled up the tank yesterday and it's still doing it, but maybe not quite as extreme as it was before I filled up.

I also thought maybe it could be the fuel filter, but I've only had the URD pump & filter installed for about 5-10K miles, so I wouldn't think it would need regular replacement yet. I just hate to go through the trouble of dropping the tank and pulling everything apart if I'm not sure that's what the problem is.

 

[NHXRUNNER]

Try the filter first, that's a much simpler fix....

 

[autobodyX]

Had the same problem my self.. pinched line. too sharp of a bend and it cracked.. drove me crazy.. PM me i will send a few pics of my fix.

 

[NHXRUNNER]

Had the same problem my self.. pinched line. too sharp of a bend and it cracked.. drove me crazy.. PM me i will send a few pics of my fix.

Please post them here. It's very easy now on the new forum software. Use the "Upload a file" link at the bottom of the reply. Or if you're on PC you can drag and drop them directly from your hard drive.

 

[Doublld]

always start at your last MOD an go from there it is a fuel isssue

 

[autobodyX]

After finding that my fuel line cracked at bend below the clamp I decided to reroute the line threw a hole closer to the center of he pump housing. Less stress on line.

 

[macg33k]

So did you end up drilling a new hole in the top of the white container? Or did you route it through an existing hole?

I didn't get a chance to change the fuel filter this weekend, but I'm planning on doing it very soon -- maybe this evening. I'll be very curious to see if that fixes my problem. Otherwise, I guess I'll drop my tank and see if the line is split in there like yours was.

 

[blackx-runner]

I would say some kind of issue with the line inside the tank. The initial symptom of hesitation to starts sounds like fuel was allowed to bleed pressure, and probably back flow out of the lines. As it got worse such as a cracked line like the above pics it would be shooting out the crack instead of making its way to the engine. That would certainly cause your loss of power.
I wouldn't do too much driving, especially under much load, until you get it sorted out. Run it lean under a load and you're liable to have a bigger problem.

 

[Torspd]

So did you end up drilling a new hole in the top of the white container? Or did you route it through an existing hole?

I didn't get a chance to change the fuel filter this weekend, but I'm planning on doing it very soon -- maybe this evening. I'll be very curious to see if that fixes my problem. Otherwise, I guess I'll drop my tank and see if the line is split in there like yours was.

Take pictures of what you find. It'll be good to share and see.

 

[macg33k]

Well, I just replaced the fuel filter and took it for a test drive. And things are still bad.

Looks like I'll be getting some submersible fuel line and dropping the tank. I suspect I'll find the same thing as Mike with a cracked fuel line. Mike, lemme know if you ended up drilling that hole in the white bucket or if it was already there.

Really not looking forward to having to drop the tank.

 

[macg33k]

Just found this thread over on TW that's making me think I should just get the flexible plastic tube (like the factory in-tank line). Seems like it might be a little more durable since so many people have had problems with splitting the rubber line.

 

[autobodyX]

So did you end up drilling a new hole in the top of the white container? Or did you route it through an existing hole?

I didn't get a chance to change the fuel filter this weekend, but I'm planning on doing it very soon -- maybe this evening. I'll be very curious to see if that fixes my problem. Otherwise, I guess I'll drop my tank and see if the line is split in there like yours was.

It was a existing hole but I made it bigger. It is easier to remove the bumper and slide the bed back rather than dropping the tank. iMO. This is the replacement line I used.

 

[macg33k]

Interesting idea removing the bed instead of dropping the tank. Seems like it would make it a lot easier. Plus, I've got a full tank of fuel right now so I really don't want to have to lower and lift that thing.

Maybe I'll get myself a T55 torx driver and go that way instead.

 

[macg33k]

Welp. So I pulled everything apart (decided to unbolt the bed instead of dropping the tank). And what did my wandering eyes see when we bulled the fuel bucket from the tank? A split fuel line, just under the hose clamp at the top.

So, I replaced the Gates hose with the plastic factory-style fuel hose and put it all back together.

Now, here's where it gets interesting. My loss of power/hesitating issue is greatly reduced, but it is still there, starting up around 3-4K RPM. Truck begins to lose power and feels like it is missing.

Needless to say, I'm fairly baffled...and very frustrated. I'm sure I tightened down the hose clamps on that new plastic hose. I also tried unplugging the battery for about an hour to reset the ECU. Maybe the next thing is take a look at the spark plugs and see what kind of shape they're in.

 

[autobodyX]

I have little faith that style clamp will seal that plastic line. You have the same leak just not as bad. Imo

 

[Gadget]

URD has changed the type of clamps we use in the pump/filter kits. The ones we use now cannot be over tightened and harm the hose.