Well I installed my DIY ITB's and started the car, It runs really rough and I am getting backfire from the ITB. When I rev it to about 2,000 rpm I get a blue flame backfire from cyl.3 through the ITB. I checked the timing and the TPS and Map sensor and all are on mark or voltage. I am using my P13 ECU and not throwing any codes. It backfired and popped off the ITB's, any suggestions would help.

 

Probably running rich due to your new vacuum readings with the ITB's...

 

It seems that I am running rich because the exhaust fuems smells rich. I tried lowering the fuel pressure but when I do it seems to not get enough gas and dies. My FPR gauge is reading 40psi.

 

TTT

 

I don't know what the problem could be...but you should try and get a picture of this in your garage with the lights off. That would probably look really ******* cool

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b16a ferio &raquo;</TD></TR><TR><TD CLASS="quote">I don't know what the problem could be...but you should try and get a picture of this in your garage with the lights off. That would probably look really ******* cool </TD></TR></TABLE>

 

It's the fact that you're running rich. We have occasional backfires as well on stock ECU's.

 

I was thinking of setting my FPR to 30psi, do you think that is to low?

 

you should have invested in a wideband o2 sensor what you can do is adjust the fpr a little, hold it at like 2k rpms for a little while, then turn off the engine and pull the plugs, you should be able to tell the fuel mixture from that. do yu have a cat on your car? if not you should see black smoke from the exhaust.

maybe its the opposite, maybe your running lean, more air from the itbs may equal more fuel needed. i would use a real tuning tool, at least an safc. other than that im not sure, sorry. let us know if you figure something out.

ps what engine are you running? h22 as in your sig?

 

Well I took off the ITB's today to take another look at them to make sure that I wasn't missing anything but it looks like they are fine. I am going to get silicone hoses to replace my rubber ones that I had on there, I'm thinking that the rubber ones got soft with the heat and maybe caused a vacuum leak. When I put them back on I am going to lower the fuel pressure and advanced the timing to see if that helps. I know there was someone else that was having a psh-psh-psh noise coming from there ITB's and mine are doing the same thing. He said he plug up the holes and it runs better, I PMed him to find out what exactly the holes he plug so I'll see when he gets back to me. So for right now back to square one.

 

i would make sure you have enough vaccume for the map .....mabye think about a vac canister

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by machine4321 &raquo;</TD></TR><TR><TD CLASS="quote">i would make sure you have enough vaccume for the map .....mabye think about a vac canister </TD></TR></TABLE>

I made a vac can out of 7inch long 2inch diam. PCV and put the fittings to and ran all the line to it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98HB &raquo;</TD></TR><TR><TD CLASS="quote">

I made a vac can out of 7inch long 2inch diam. PCV and put the fittings to and ran all the line to it.</TD></TR></TABLE>

clever, snap some pics of your whole setup if you can, a video would be awesome.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98HB &raquo;</TD></TR><TR><TD CLASS="quote">I know there was someone else that was having a psh-psh-psh noise coming from there ITB's and mine are doing the same thing. He said he plug up the holes and it runs better, I PMed him to find out what exactly the holes he plug so I'll see when he gets back to me. So for right now back to square one.</TD></TR></TABLE>

pm sent

 

ur vaccum is plenty big. Im to the conclusion that ITB's werent ment to run super dandy on our stock ecu's...
Mine is driveable, but it backfires, and misses every so often. I dont like driving it like this..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Swags04 &raquo;</TD></TR><TR><TD CLASS="quote">ur vaccum is plenty big. Im to the conclusion that ITB's werent ment to run super dandy on our stock ecu's...
Mine is driveable, but it backfires, and misses every so often. I dont like driving it like this.. </TD></TR></TABLE>
But my problem is that I can barely drive the thing. I was thinking on getting the golden eagle vac log to see if that changes anthing, but it would suck to spen the 50 bux and have it do the same thing.

 

I dont think there's anything that an ITB install could cause that would make your motor backfire thru the intake side. Check your timing belt, recheck ignition timing, recheck map and tps... Check yur distributor, cables, plugs, etc, make sure the miss isn't being caused by an ignition problem.

 

I'm no tech guru, so forgive me if I'm being an idiot, but if the problem is with the stock ECU, why not just get something else that will work better? Sure, it'd be more money, but then your car would be running correctly.

 

I ran mine off a chipped ECU, and I think stock would be worse. I tried a vacuum log type set-up, but it wasn't much better. I'm thinking a afc hack could fool the map sensor enough into running lean, where all you would have to do is add fuel. You have to find a way to alter the map sensor voltage or vacuum.......kind of like how you have to mess with the map when running a turbo. Of course an engine management system would be the best......

 

I have another ECU (p28) that is installed with Hondata s100, but I haven't been able to try it because it's a Euro ECU and I keep throwing coed 13 and 16. I'm waiting to get another chiped burned and will see if that helps. BTW my p13 is also chiped.

 

Problem is you have no vacuum at light throttle and the stock ecu is trying to dump fuel and take timimg out at the same time . You will need to either run a standalone or Hondata . I use Crome and it works too but ITB's are not know for ther smooth throttle transfer so dont except it to act like a plenum manifold .

 

I am going to plug the vacuum holes on the ITB's and drill holes in the runners of the manifold and run my vac source from there. Hopefully I can get a better vac reading. I'll try to post pics of the vac log and when I tap the runners.

 

Had that problem today while on the dyno! Our problem was that were not getting enough fuel.

Fixed the fuel issue and cranked her right up.

The set-up uses the GE vacuum block, but sounds like yours is fine. My set-up is a bit different now, but when I had the chipped P28, we had the IACV plugged up but haning there zip tied, and had the map sensor running off the vacuum block. NO Check engine lights at all. Ran 310cc Injectors as well. Ran just fine. With my set-up now though I mos def needed to get on a dyno and finally did today.

We put down 232.7 FWHP w/ 145.1 Torque. We didn't get to finish it though ran out of time. I was happy though A/F was stout beutiful! Power all the way just past 9000rpms.

Actually its was 232.7 @ 9000rpm
w/ 145/1 @ 7750rpm

Good luck!

 

(velocitytrends) Great numbers!!.

 

Thanks