Stuttering and stalling under boost after fmic, built head with 272's, o2 housing

[96gstdsm]

Got my car back and now when under boost it stutters a bit. It will also stall out when I come to a stop sometimes. Sometimes it will idle fine, other times it will start dropping and then shooting up to like 1500 then back down to 300 etc till it dies out.
When I got to really get on it a bit and it gets into boost it will hesitate and stutter first then get into boost and be ok. Just pretty much the initial getting into boost that stutters bad.
I think the idle is set around 800 or so. Seems to switch depending on how long it has been on so hard to really say. Kinda switches between 750 and 1000 when not dying out.
Would untuned cams do this? I also have some skunk 2 adjustable cam gears zero'd out.
My car did not have any idle problems after I got a 6 bolt block put in with a 190 pump rewired. I then brought it back for the rebuilt 7 bolt head with bc 272's, o2 housing, front mount, and a 3" downpipe and it has been happening since then. I have been monitoring everything with ecu+ so I can datalog if that would help finding out what is wrong.

Any suggestions would be great.

 

[92 GSR-4]

Yeah it is set for the 450's right now. Do you know what you think would cause the sputtering? It only happens when getting into boost. Once I get boosting a little more then it stops sputtering for a little bit and I take off. And then when I slow down and repeat same thing again.

I can't say that I know whats causing the sputtering. However, I would suggest fixing a known problem first, the ISC, and then move to the next.

 

[96gstdsm]

What exactly does lifter tick sound like? There is a ticking or knocking noise coming from the engine. The guy said it was bad lifter tick, but it has quited down some. I bought revised lifters, so didn't think they tick.
What I'm hearing just goes tick tick tick kinda loud though and more of a knocking kinda sound then quite tick.

Just googled some video and the guy said he had lifter tick and from what I could tell it sounded pretty similar to what I'm hearing in my car.

 

[96gstdsm]

Well just got back from the dyno tuner. For some reason they said they couldn't connect the computer to the ecu+ for tuning. So I gotta see why that is. Would just freeze up the laptop.

The messed around with my idle. Told me it was not the ISC.
Told me that they just needed to adjust the fuel for the idle. After I left I checked my ecu+ datalogger. They just raised the idle to 1000 rpms. Also they put the load to high load.
And also adjusted the MAS to -13. The injector scaling was left at 450 cc for stock and 450cc for current. They put in the 650cc injectors. So I switched that to 650cc injectors, and the idle got kinda crazy, and sounded a lot more lumpy and lopey. It died out eventually after a little while.
I am assuming it is dangerous to leave it this way right? I really don't know where else to turn at the moment as I don't especially trust myself to tune it. I also don't have a wideband o2 sensor yet.

Anyone wanna make some money tuning hahaha? It also stalled out once while the idle was set at 1000, it idles even though set at that usually around 1200.

Now also anytime I got into boost at all, it would just stutter much worse than before and I could not boost at all. Would that be from running rich? I have not tried running it since I changed the setting to 650cc injectors for fear of blowing something up.

Let me know any suggestions.

 

[oldman]

So you paid Turbotrix $400 for nothing?

Did you finish the boost leak test before going to the shop? Have you tried adjusting your BISS like I posted?

 

[96gstdsm]

So you paid Turbotrix $400 for nothing?

No atleast I didn't pay them for any tuning. haha Would have flipped if that happened.
Made me pay them 90 for the damn injectors though haha, but had no choice as I didn't want to drive down there with them in for fear of screwing up the afr.

Now I'm totally stumped of what to do next. I really don't know why they couldn't connect to the damn program. It works fine with my pda but have never tried with a laptop yet.

I haven't been able to do a boost leak test yet, I lost my one I used to have and now I can't find the right size coupler thing at home depot, don't know where else I can find one locally.
I don't really have any tools to adjust the biss myself, since you said I can't just turn it back. So will have to bring it somewhere to have them adjust it and check that out.
Turbotrix said there was nothing wrong with the ISC, but who knows. There is some sort of electrical ticking sound going on while idling sometimes, don't know what that is.

 

[oldman]

Put your 450s back and remove the ECU+, get your mechanical issues resolved first. You have already been given many suggestions of what to do next but you choose to ignore them because you're looking for an easy answer, instead you choose to listen to someone who charged you $90 to install 650s and set your ECU+ to 450s. Don't ask for advice if you're not going to take them seriously, you have pretty much done everything that I have advised against and nothing I have suggested, 3 days and $90 later, we are back to where we started.

 

[96gstdsm]

Ok fair enough.

I will swap out the 650's. I will try at first leaving the ecu+ in as that was in when I first got the car back and had no problems. Nothing was changed with that. I'll have to bring it somewhere as I have no type of scan tool for correcting the ISC.

Since the stuttering got much worse after the bigger injectors, would the most likely scenario be that it is just running really rich? Was kinda bad with the 450's but now with the 650's I can't boost at all. Just bogs down real bad and stutters like crazy. I have to take my foot off the gas right away and keep out off boost the whole time.

Do most shops have scan tools to correct the ISC? Or would I need to go to the dealership or something?
Have hardly any free time on my hands for myself to work on it that is why I have been trying to take it somewhere to just finish it up. Been 3 months now working on this car, so need it done really at any costs at this point.

I will see what happens when I put the 450's back in and also when I take it to a shop to check the ISC.

 

[92 GSR-4]

Oldman is right. You shouldn't mod the car further in hopes to fix an unknown problem. It's just silly. It sounds like the tuning shop took advantage of you and sold you 660's knowing fully you had problems and that wasn't going to fix it.

Still you refuse to take ECU+ out to see if your problem clears. And now you've got a set of 660's in the car to further complicate things, when you finally do take the advice and yank the ECU+ out of there. Swap the 450's and a stock ECU back in, and make sure your using a 2G MAF...and be amazed. I have a feeling some problems will clear up.

Now, a bone to pick with you. Here is what I use to TEST my ISC. Behold:

You must be logged in to view this image or video.

This is a multimeter ($10) and a piece of everyday wire. Can you see why we get frustrated with you? Had you done a search, or called RRE or someone about the 6-bolt swap and how to set your baseline idle, then you would probably not have all the issues you have. A quick search on this site will reveal to you that you more than likely have boost leaks causing an irratic idle...but here's a VFAQ to set the baseline: http://www.vfaq.com/index-main.html

Listen to people who know what they're talking about. A DSM Wiseman is usually a good source (read: Oldman). But most of all, do alot of reasearch. Focus on one problem at a time and eliminate them one by one. Eventually they will be gone.

-Seth

 

[96gstdsm]

OK well I removed the injectors and put my stock ones back in. I also removed the ecu+ engine management system. I had the ISC tested and checked again. Came out fine. I boost leak tested it and came out good with no significant boost leaks.
After taking the ecu+ out and the injectors it seemed to be fine for a few pulls and a little drive. Then drove it back home and the idle started bouncing again. Was not stuttering at all though, think I hit fuel cut a couple of times trying to set the boost to around 14 psi or so. Got it down around 13 and seemed good. This was a couple days ago. Now when driving again when it starts getting into boost it will stutter again. Was much worse with the 650, could not get any boost but now will stutter and then boost.
It will also always die out again at idle. When I push the clutch in it seems to get worse and drop some more.
Anything else I should check for?I unfortunately have no way to log right now since that was part of the ecu+.

 

[96gstdsm]

Ok well thought I had just found the problem. I found the line going from the wastegate actuator to the mbc was completely severed. I put in a good vacuum line and at first again it seemed to fix the problem. Went for one trip out for a few miles and boosted great with no stuttering. The idling was still messed up though. Was bouncing around a little and then completely stalling again. Took it out again and this time it started stuttering again. A little at first and then more and more. Seems like once the car has been running a little longer it starts stuttering. It got much worse with the bigger injectors also.
Anymore ideas what to check for with this? Driving me crazy here. Tried bringing it to a couple shops to see if they could figure it out but they all suck!

 

[m_0ney_pit]

Mine is doing the exact same thing since I got done with the install, I figured it was just the BOV not being recirculated causing this. Under closed loop the car pulls great though!

I don't think SSAC could have picked a worse place to weld the BOV flange...

 

[96gstdsm]

Mine is doing the exact same thing since I got done with the install, I figured it was just the BOV not being recirculated causing this. Under closed loop the car pulls great though!

I don't think SSAC could have picked a worse place to weld the BOV flange...

I have mine recirculated with no problems there. Seems to be in a fine location for me.

 

[96gstdsm]

Well not sure if this was the cause to the stuttering or not. Seems to be though. After tons of time checking and replacing misc. parts. I opened another thread regarding my car all of a sudden shutting off and not starting up again. After checking a bunch of things, I found that the power wire for the fuel pump had gotten disconnected.
I only drove the car for about 60 miles since reconnecting it, but so far my car has not stuttered at all, and has felt very nice and smooth throughout every gear. I am really hoping this was the main problem I have been having with my car.
If it was a bad wiring connection for th power wire on the fuel pump, would that cause it to stutter?
Also when bigger injectors were put in for a short period it got much worse(unable to boost) could the bad connection cause that due to needing much more fuel than the power was supplying?
Either way at least I am able to drive my car right now which is a huge relief. Hopefully the stuttering has also been cured, but I have learned not to get my hopes up to fast.

 

[96gstdsm]

Ok well it has started sputtering again after about 2 weeks. Now it sputters real bad when going WOT. What could keep coming and going with this stuttering? Been going on forever. I fix one thing and it seems to go away for a while and then comes back. Then I fixed the tps which was loose and it went away. Came back and I fixed the fuel pump wiring. Went away for 2 weeks and now is back.
I have no cat. It smells strong of fuel. How strong of fuel is normal with no cat? Maybe I am running rich and fouling out my spark plugs? Even though I have stopped momentarily the stuttering without changing the plugs. I am actually going to be selling this car soon so I really gotta get it up and running well to get some money out of it. Could having a 190 fuel pump and no fuel regulator cause anything like this? When I switched over to 650 injectors it made it impossible to boost and just bogged down real bad. It was not tuned however at the time. I still have not tuned it since the new engine and turbo and fuel pump and all. But running on stock ecu at around 15 psi.