Jump to content

Tuned ECU, lean, help!!!


Diamonds

Recommended Posts

[quote[

Though seems odd that it ran richer, at points, before on higher boost and no boost controller.

[/img]

 

I know, whats your best guess??

 

 

 

Wait, at 8psi it is running 13.5 afr? That isn't rich. I'd rather see low 12 to high 11. I really don't see it pegging MAF since its the stock turbo and MAF. From factory, doesnt it run 8-12.5 psi? I can't remember. I think the one in my garage is putting out 8psi factory set (so I believe factory set). That engine easily did 11-12 afr on stock t28, MAF, stock injectors, and stock fpr at 12psi. Might want to double check wideband, fuel pressure under boost, and possible small vacuum leak. Though seems odd that it ran richer, at points, before on higher boost and no boost controller.

 

And about the boost referencing fpr, it is a regulator that increases pressure when under boost. They can vary in different ratios from 1:1 to like 15:1, meaning that for every psi of boost, it could increase fuel pressure 15psi. Normally those high ratios are used on cars with stock fuel maps/injectors (poor boy fuel "tuning"). Now about your Walbro pump, is it the high pressure one or low pressure pump?

 

I dont know what it runs from the factory... apparently it runs 8psi... because thats what mine is doing (s14 t28).

 

I think the order of events will be this....

 

Today i am going to hook up a Fuel pressure gauge so i can see fuel pressure in the cabin. My bet is that (under boost) the Fuel pressure will not rise from 3 bar-ish (45-49psi at idle)

 

Does that mean the FPR is bad? or does that mean that the pump is fucked?

 

I dont know if its high pressure or low pressure (walbro)... its the 255lph... how can i tell?

 

 

 

 

 

 

13.5 is rather lean in boost. it's not a stock turbo, and i assume youre probably running a soch maf, which contrary to popular belief, has a different transfer function than the actual sr maf. which t28 turbo are you running(s14 t28, s15 t28, s15 t28r, gt28rs)? also what is base fuel pressure set at? I believe stock is 43-45 without vaccum. jump your fuel pump relay and check it. that fpr you have looks rather chincy. I'd investigate it further. i still think the lower injector bosses you have could be leaking (ive seen it happen on every sr we've tuned/worked on without them being welded in). crank fuel pressure up to 48-50psi base and see what afr's are? the emance tune is a decent one. the few cars ive worked with, with the emance mail order tunes have been pretty close, the timing maps are rather conservative though. I would check everything over (boost leaks, FP, etc) and see where you are from there.

 

s14 t28

 

David, i have a question regarding the EMance.... IF i change to a z32 MAFS... how will that affect the already tuned ECU?

 

what is an injector boss? is that the round washer by the tip of the injector... can you post a picof a welded one?

Link to comment
Share on other sites

Swapping the maf out is not a good idea. they have different transfer functions than the soch and sr maf.

 

http://s4.photobucket.com/albums/y124/Stebbins97/?action=view&current=341296_620995709620_215904336_33191783_6898295_o.jpg

 

this is the only picture i could find of them. have someone weld those aluminum donuts into your intake manifold. i dont know if an s14 t28 turbo would peg out a maf or not. buddy of mine ran an s15 t28 on his car forever with no tune and no problems. if you have a set of stock injectors i'd pull the 550s out before you weld the bungs in and try that? you'll need a stock ecu though.

Link to comment
Share on other sites

It is hard figuring these things out without being there. lol, might need to get back with what your fuel pressure readings are. Also, anyway to double check afr with another wideband? I know my friend has had issues with his Innovate giving him false lean conditions, very similar to what you were saying.

 

Also, I am not sure how to check about whether the pump is high or low pressure. I don't know if the things are marked on the pumps that way.

Link to comment
Share on other sites

Here's some new development..... MY FPR does have a vacuum fittign on it... BUT, after finding out that its probably a MEGAN racing FPR... it does not in-fact reference boost... so that MAY be the problem.

 

 

can someone reccomend me a rise rate boost Referenced FPR that costs about 100 bucks?

Edited by Diamonds
Link to comment
Share on other sites

Actually that Megan racing fpr could be a rrfpr. But Aeromotive makes fantastic rrfpr. I think I even have a 13109 fpr sitting around from the sr20. I pulled it off to run factory fuel set up, and previous owner installed it incorrectly. But if you go buy one, make sure you get the fittings and hose to hook it up. To make it easy, get the twist tite fittings/hose.
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...