Options for more fuel

[SicSE]

I'm leaning out a bit at higher RPM's and want to weigh my options to get more fuel to my 98 return-style system. I'd rather not go the fuel pump route, though an inline booster might be a possibility if people are running them with success and they're not too noisy. Would an add-on pressure regulator be a viable option? Can the stock regulator be modified to up pressure? Are all the return style rails the same? I think a larger diameter rail may fix my issue but I'm not sure if one is available. Any help is appreciated.

 

[BrApple]

since you are still running stock 17# injectors an upgrade and tune for 19# injectors would be a good start ....


do you have an early 98? if so get a RJL1 SVT PCM with 19# injectors and you will not even need a tune .... I know of one available in the classifieds.

 

[SicSE]

The injectors are keeping up for now. Before I get bigger ones, I need to make sure I have the fuel to feed my current ones.

 

[BrApple]

The injectors are keeping up for now. Before I get bigger ones, I need to make sure I have the fuel to feed my current ones.

factory fuel pump is fine for a 3L and 19# injectors .... bottom line a 3L should be run with a minimum of 19# injectors, they can run on 17's but perhaps you are seeing why they shouldn't be used .... and a SVT PCM. Its program is better for running a 3L also. I saw the difference between a SE and SVT PCM, the SVT one was better ....

 

[BrApple]

I just read your FCO thread, I have to agree it doesn't sound like a fuel issue at all. the stock fuel pump is more then enough for a 3L ....but have you checked the fuel pressure at the fuel rail?

 

[SicSE]

I don't doubt that the SVT PCM is better. I also understand and agree that it will be better with a tune. Unfortunatley, unless my PCM itself is the problem, I don't see how bigger injectors and a tune and/or different PCM could possibly fix this issue, given the details and the data I'm logging.

Fuel pressure holds steady @ 55psi. But that's at the schrader valve and that is the first point to get fuel from the tank so it's only a small part of the picture. With bank one staying rich, fuel pressure isn't much help.

The problem does not follow the injectors, the plugs, or the first O2 and is still there with a new coil. The whole bank is slowly leaning out and you would be able to feel a singular missing cylinder. A cam timing issue would always be there and be evident in fuel trims. There is only one remaining possibility as far as I'm concerned and that is fuel starvation.

I have never said the pump was my problem but everyone seems to be interpreting "fuel starvation" as me saying that the pump is inadequate. I may need to be looking for an obstruction or kink in a line. Perhaps my pump is on it's way out... not unheard of on these cars. Regardless, my problem is fuel related in my mind and now I have to find out what exactly is causing my lean condition. A bump in fuel pressure or flow is the easiest next step to try and verify my theory or prove myself wrong.

What's the easiest and/or cheapest way to bump fuel pressure?

 

[BrApple]

but you are already getting good fuel pressure :shrug: your not going to loose an appreciable amount of pressure between the schrader valve and the injectors. Also fuel pump failure isn't that common ... yes the returnless system cars tend to have the sock on the pump gum up and cause problems.

swapping the your stock pcm to the SVT one is like a tune, it has a different fuel map and timing curve, its more adgressive. but to use the SVT pcm without getting lean codes on both banks you need to also install 19# injectors as the PCM is calibrated for the injectors.

when you swapped the O2 sensors you did reset the PCM and drive it for a few days right?

 

[Rara]

What's the easiest and/or cheapest way to bump fuel pressure?

Well, you need to do it accurately, or both banks will just go rich, and you won't be able to tell anything about the root cause. About the only way to do that is with a proper adjustable fuel pressure regulator, which isn't cheap. Even then, you would just be applying a bandaid to cover whatever the real problem is.

You either have a problem with fuel delivery, air delivery, or control.

If its fuel delivery, you've determined that it probably isn't the injectors, and it probably isn't the pump either. The rail pressure would generally start to drop if you have a pump issue or a filter issue, and you would definately see it at the schrader valve. The only remaining stone here to turn is the fuel rail itself. Have you tried replacing the fuel rail with a known good one? Or at least cleaning out your rail?

If its air delivery, have you checked the inlet tract for any obstructions? Have you performed a leakdown? Perhaps you are blowing fuel rich air right out through a leaking exhaust valve ,or introducing fresh air into the exhaust ports. Do you have any leaks in the exhaust manifold? Do you have any vacuum leaks? Are you sure? Are you really really sure?

If its control, its probably because you are using injectors that are borderline for a 3L. (from Brapple's posts i assume you are running a 3L w/ 17# injectors and the stock SE PCM) 17lb injectors are not enough on a 3L, because injectors don't control nearly as well once they go over 80% duty cycle. You should be using a minimum of 19lb injectors for that setup, and have the pcm properly calibrated to match (SVT PCM + SVT injectors is the easiest way to do this for you). Injector issues that are so close to the borderline like this can be made worse by an old wiring harness w/ too much resistance as well.

All that said, my money says you probably have a leak somewhere, and you are having calibration issues because you are using a stupid combination of PCM and injectors for a 3L.

 

[Rara]

Ok, I couldn't resist, and I went over and read the FCO thread . . . LMAO, this is funny stuff. couple more thoughts.

1. Dom and I may have had some technical disagreements over the years, but he's done a lot of 3L swaps, and generally they are at least capable of running all the way to redline without falling on thier face . . . and it appears in this case we've both come to similar conclusions about your setup.

2. Even Terry and Dom think you are an arrogant ass . . . That's quite an accomplishment.

3. Check ultra carefully for vacuum leaks again, then do it one more time. Then, have someone else check again, because you are probably missing one. Then install 19# injectors, and an SVT PCM (or have your SE PCM properly recalibrated) and your car will run fine, and probably make a noticable power improvement throughout the entire range.

 

[SicSE]

when you swapped the O2 sensors you did reset the PCM and drive it for a few days right?

That's not necessary since I'm going off of the reading right from the O2. I only swapped the O2's to make sure it wasn't the O2 itself misreading. If the O2 was the problem, the bank reading lean would have followed the O2 under these conditions.

Have you tried replacing the fuel rail with a known good one? Or at least cleaning out your rail?

I only just thought of that about an hour ago, so I have not done it yet, but it IS the priority at this point.

If its air delivery, have you checked the inlet tract for any obstructions? Have you performed a leakdown? Perhaps you are blowing fuel rich air right out through a leaking exhaust valve ,or introducing fresh air into the exhaust ports. Do you have any leaks in the exhaust manifold? Do you have any vacuum leaks? Are you sure? Are you really really sure?

A valve that wasn't seating completely would give me a miss at idle, so no, I have not done a leakdown.
An exhaust leak large enough to throw off the O2 would be audible. Plus the pressure in the exhaust at WOT at 5K would not allow the accidental introduction of fresh air.
A vacuum leak would be more prevalent at idle and would certainly affect fuel trims. So no, I do not have a vacuum leak, yes I'm sure, and yes I'm really really sure.

If its control, its probably because you are using injectors that are borderline for a 3L. (from Brapple's posts i assume you are running a 3L w/ 17# injectors and the stock SE PCM) 17lb injectors are not enough on a 3L, because injectors don't control nearly as well once they go over 80% duty cycle. You should be using a minimum of 19lb injectors for that setup, and have the pcm properly calibrated to match (SVT PCM + SVT injectors is the easiest way to do this for you). Injector issues that are so close to the borderline like this can be made worse by an old wiring harness w/ too much resistance as well.

All that said, my money says you probably have a leak somewhere, and you are having calibration issues because you are using a stupid combination of PCM and injectors for a 3L.

All very valid points and thanks for your input.

 

[kscontourkid]

Fuel pressure holds steady @ 55psi. But that's at the schrader valve and that is the first point to get fuel from the tank so it's only a small part of the picture. With bank one staying rich, fuel pressure isn't much help.

what is wrong exactly with your car? what is it doing or giving you codes for. i may be able to help as i have a 3L swapped into my SE and have had many pain in the arse problems with it...still am. i have fixed most of the issues. what your are saying sounds very much like my issue. one bank lean one bank rich... check your EGR valve. i had to cap mine off because the egr system was not cooperating. maybe this information will help you maybe it wont but if you are having these symptoms try it.

right i just read your post on FCO and immediately your symptoms matched mine. block off your egr and see what happens. both banks should go lean with the 17# injectors at about 5K. you have a leaking egr valve more than likely and the extra unburnt fuel is coming in the bank 1 side. cap off the EGR and see what happens

good luck

 

[SicSE]

Even Terry and Dom think you are an arrogant ass . . . That's quite an accomplishment.

I've been called much worse. I just don't let people talk to me the way Dom talks to people. Plus I don't like when people state their opinions as fact and are closed-minded. He's not used to someone standing up to him so it's a problem when it happens... especially if that someone actually knows what they're talking about... and then proves him wrong, (take a good look at our fuel rails). Ugly stuff. I've seen menstruating women that argue less & stay on topic more... and that's saying something!

Check ultra carefully for vacuum leaks again, then do it one more time. Then, have someone else check again, because you are probably missing one.

Seriously. i hope I don't sound like an ass here, I DO appreciate the input and you seem like you know your pretty well. But I really don't have a vacuum leak. If my word is not enough, know that I work with about 6 senior master techs, which is the highest title a Ford tech can have, who all agree with me. I myself have to do driveability to fix any issues on engine installs. Among the 30 or so vacuum leaks that I personally have seen and diagnosed over the years, and the countless vacuum leaks that the guys I work with have seen and diagnosed, 100% of them had an effect on fuel trims, and 0% were only present at WOT, high RPM, high load. Every one on every single engine platform. If that is still not enough, take your own experience. Think about the vacuum in your intake. It's higher at idle than at WOT. A vacuum leak could not possibly ONLY show up under WOT load, high RPM in our setup. It is literally impossible. I swear to you, I promise you, I do not have a vacuum leak.

 

[Rara]

Well, I would classify an egr leak like kscontourkid posted above as fitting into my original comments of you having some kind of leak, somewhere. I'm just lazy and using the term vacuum leak rather generically.

And fwiw, I've seen some really strange incarnations of intermittant vacuum / intake tract leaks over the years, including ones that were sealed at idle, and would cause trouble as rpms increased. I've also seen intentional leaks on race engines that would only show up at higher rpms to lean things out, increasing power on an otherwise "spec" engine. The point is, stranger things have happened, and don't be so arrogant to assume that you've seen everything; I know I sure as hell haven't.

So go fix your apparent EGR leak and install some SVT injectors and PCM.

 

[SicSE]

what is wrong exactly with your car? what is it doing or giving you codes for. i may be able to help as i have a 3L swapped into my SE and have had many pain in the arse problems with it...still am. i have fixed most of the issues. what your are saying sounds very much like my issue. one bank lean one bank rich... check your EGR valve. i had to cap mine off because the egr system was not cooperating. maybe this information will help you maybe it wont but if you are having these symptoms try it.

I'll be damned... that's a hell of a suggestion that I didn't even think of and it would explain everything... especially since I have a stock exhaust. I can imagine the pressure pushing on that er up high. Thanks man - you just gave me a new priority.

 

[SicSE]

The point is, stranger things have happened, and don't be so arrogant to assume that you've seen everything; I know I sure as hell haven't.

You've got me all wrong. I'm the first person to admit when I'm wrong and that I don't know everything. I just don't do well with being purposefully and undeservingly disrespected.

 

[kscontourkid]

cap it off with a small piece of aluminium and double gasket. i have to replace my egr sensor cause it still thinks exhaust gas is flowing and i have a very small exhaust leak somewhere and i cant find the damn thing but i havent looked extensively yet. check that out and see what happens. that should fix it then get some 19# injectors to solve the lean issue and tune your pcm for them. then you will have a rocket

 

[SicSE]

I'd rather keep the EGR valve so I may just get a new one... although part of this, if it IS the problem, could be excessive back pressure so I'll check that as soon as I can too. That may move up when I do my exhaust.

I already have the 19# injectors so I just need to find a PCM... anyone want to sell a PCM to an arrogant ass? :laugh:

It already feels pretty strong, (172/184), so I'm pretty anxious to see what it'll put out when it's done.

Thanks for the help all.

 

[kscontourkid]

what im saying is cap it off to see if its the problem. i agree with you id like to have my egr back but right now i dont have the time or patience to change the egr valve. by capping it off you will find out if it is indeed the problem then you can work from there.

on the pcm... i would suggest getting your stock pcm tuned. go to joey(burritaSVT) and tom(warmonger) and get a tune off them. they are top notch and will drag out every inch of power from your engine.

 

[BrApple]

I'd rather keep the EGR valve so I may just get a new one... although part of this, if it IS the problem, could be excessive back pressure so I'll check that as soon as I can too. That may move up when I do my exhaust.

I already have the 19# injectors so I just need to find a PCM... anyone want to sell a PCM to an arrogant ass? :laugh:

It already feels pretty strong, (172/184), so I'm pretty anxious to see what it'll put out when it's done.

Thanks for the help all.

I have trouble believing that the egr valve is an issue, they normally never fail ....


the is an early 98 PCM for sale in the classifieds that is for sale by cannondalemtb ...

 

[SicSE]

what im saying is cap it off to see if its the problem. i agree with you id like to have my egr back but right now i dont have the time or patience to change the egr valve. by capping it off you will find out if it is indeed the problem then you can work from there.

Thanks for braving the negativity man. This makes more sense than anything anyone else suggested and no one likes to be wrong so you know there is more to come over there.