Help with Aeromotive 1000 Pump

[1bad396ss]

I have a Boyd Welding tanks with the Aeromotive 1000 in-tank pump. While I have purchased and installed everything over the last 3 plus years, I am just now to the point of tuning everything in. My tuner cannot get the injectors to scale out even at idle. Had injectors flowed and tested - all good. Fuel pressure is 58psi at idle; however, as soon as the pump is powered down the fuel pressure drops to zero instantly (even during key on priming).

I think I have an issue with the pump. Something makes me think it can support 58 psi at idle - but I have a major volume issue (ie: it is simply not pushing volume up to the rails.

Aeromotive Pump -10AN out to -10 filter to Y- Block to -8AN into each rail, out of each rail into Aeromotive regulator with -6 return to tank.

Any other fuel injection system I have dealt with has a slow bleed of pressure after powering down - not an instantaneous dump to 0.

I don't believe the fuel regulator is the issue either as it will hold to he 58 PSI setting.

Any help / advice is greatly appreciated.

[homemade87]

My guess would be you have a stuck injector . They do not like sitting around . Even if you had them checked is sounds like they were at idle for maybe years the way I read it . The pressure dropping to zero instant is a classic sign of an open injector . Most likely the reason the tuner can not get it to scale . I would pull them out and make you a homemade cleaner tester to cycle them on the bench . I made one with a syringe and carb cleaner . Check out youtube . I clean every injector on an engine that has been sitting . Saves a lot of headaches .

Be careful if you have an open injector . It could fill a cylinder enough to hydraulic it and bend a rod and break a piston .

I would be very surprised if the fuel pump had a problem . It should have an internal check in it . But things happen .

I would clean the injectors first . If the pump is holding 58psi it is doing its job . If the injector is stuck open it is pushing way to much fuel and causing the tuner fits .

[davepl]

If you think you've got a stuck injector I'd pull the plugs to clear the pistons. Otherwise, if it fires you could hydrolock the cylinder and break the crank and all of that.

Sure sounds like it though. I have the same pump and don't remember what the pressure did.

But I will caution you that this pump is big enough that it should still hold pressure while running even if you had EIGHT injectors locked up. I was close to 100% duty cycle on my 85# and the pump was still happy. So in other words one stuck injector can't really be responsible for operating pressure problems.

[BR3W CITY]

What micron filter? Any chance your getting a restriction? You can toss a meter on the pump and see if its drawing too much current and having to push past an issue. Like Dave said, the A1000 has enough supply to overcome a lot of wasted volume.

Also, where are you measuring the pressure at?

[1bad396ss]

Injectors are perfect. They fired/flowed/leak tested/ and matched perfectly. Talked to Aeromotive and the system dropping to zero isn't the issue either as that is the normal operation of the regulator being used. So... I have a tuning issue. For some reason my computer (which is showing to be out of a 2004 HD or Van with drive by wire and 4L80E) does not like the 2 bar map or my tuner isn't familiar with the truck setup - which I find very hard to believe with the number of tunes he does and how long he has been in the game doing them. When it gets to the tune part - it gets over my head. I am getting very frustrated. If I wasn't moving, I'd rip this PCM and Harness out ($700 harness) and throw Holley EFI on it and move forward.

Does anyone out there know of any issues relating to the truck ECM's OS in regards to the VE tables not responding to the 2 bar map properly?

[BR3W CITY]

If'n my memory server correct, to run a boosted Map you need to be running the expanded operating system in HP Tuners. They have the Custom O/S 1bar, 2bar, etc.
If your computer was licensed with the extended OS (extra credit cost), then it just needs to be flashed with the 2bar OS. That should allow the VE to have the expanded resolution.

[davepl]

Originally Posted by 1bad396ss

Does anyone out there know of any issues relating to the truck ECM's OS in regards to the VE tables not responding to the 2 bar map properly?

Not to be "that guy", but did you update the ECM to reflect the 2 bar bap? If not, it's getting signals that are best case 1/2 off, and worst case totally wrong. With an aftermarket EFI it's usually a simple drop-down setting, but with HPT you might need their hacked OS. I've never tried it but the menu items are there. Not sure if the separate OS requires a different or additional license though.

[Super73]

Is your regulator before or after the fuel rails?

I have first hand experience of fuel pressure falling off a cliff when it is before the rails (same regulator but different pump).

What happens is when the regulator is before the rails, it has to try and switch fuel from the return to the rails quicky or you get a fuel pressure drop as the motor takes a big gulp of fuel.

Putting the regulator after the rails it only has to return what is not being used.

[1bad396ss]

Regulator is after the rails. I believe it is a tuning issue - which I know this guy has tuned for countless folks over the years. I think he is simply having an issue with the truck ECM referencing the 2 bar map as mentioned. But I also know he has tons of experience overwriting OS etc - but I'm just not sure why this year/drive by wire / ecm / etc is stumping him.

I am going to throw in a set of injectors on loan for testing; however, given he cannot get the VE table to expand - I think he is having OS issues and not correctly "tricking" the ECM to expand and allow for proper scaling.

I'm close to giving up and going Holley EFI.... But I hate to let this beat me when I am so close to wrapping up a 5 year project - I just want to enjoy it.

Is there a way to share a starter file for a 2004 DBW Truck/Van ECM with 4L80 2WD with 2 bar map and call out exactly what OS I need him to attempt. I really appreciate any help. I also don't want to dump more money into another tuner without confidence that something isn't truly off.

[BR3W CITY]

I'm not sure what he's having issues with in terms of getting the table to scale. He needs to make sure the ECM is licensed to the custom OS (like I said, it has an extended credit cost). If you haven't paid for extra HPT credits, than you probably don't have the OS.

Otherwise he just needs to overwrite with the 2bar OS and then check that his tables are scaled (they will be labeled up to the new 2bar limits, so you can tell just by looking at it).

[Trackman101]

Your fuel pump and injectors are fine. You may need to get a second opinion on the tune.

[1bad396ss]

Given that he clearly stated he didn't see the VE tables expand - I'm going with I have a tuner issue.... I'll see if I cannot discuss further with him - wish I was better versed in this but I should be enough to get by. BR3W CITY = I am going to PM you if you don't mind.

[Super73]

I missed the part about not seeing extended VE. Sure sounds like the 2bar did not take.

I assume he wrote the entire file and not just saved changes?

[Hart_Rod]

Originally Posted by 1bad396ss

Given that he clearly stated he didn't see the VE tables expand - I'm going with I have a tuner issue.... I'll see if I cannot discuss further with him - wish I was better versed in this but I should be enough to get by. BR3W CITY = I am going to PM you if you don't mind.

You have to update the VE table you do a custom OS, as all it does is change the row lables. Send me your email and I will send you a copy of mine.

EDIT: Here's a couple pictures.

[1bad396ss]

Well turns out the first tuner was lazy or simply not as good as originally thought. Another lesson learned and money spent - very aggravating to say the least. Shane Hinds - tuner from Glen Carbon IL - knocked it out of the park. Fun to drive just on a baby 8lb tune. Cannot wait to button everything up, finish some more shakedown miles, and dial this thing up.

When you think you have researched your tuner - research more!