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whereda40at
10-16-2013, 11:08 PM
I have been trying to get this car to run good. It hits a wall any time the car goes into boost. I have tried the IAVC, MAF and ecu. Can you watch the video and see if you can figure it out or if you had the same issue, what you did to fix it? I have not found any boost leaks or problems with the wiring.

Also, after you have watched this video, check out the other videos I have of my 10 second gt28 s13 sr. Holds the world record.

Rb25 z32 running bad - YouTube (http://youtu.be/cXBIVNJGin8)

Rb25 z32 running bad - YouTube (http://youtu.be/cXBIVNJGin8)

Rb25 z32 running bad - YouTube (http://youtu.be/cXBIVNJGin8)

whereda40at
10-17-2013, 12:02 PM
Anyone have an idea?

whereda40at
10-29-2013, 10:47 AM
Anyone know where I can find a better write up to reset the timing on a rb25 s2 than in the fsm?

PrimeDirective
10-29-2013, 11:07 AM
Are you even running on all 6 cylinders?

whereda40at
10-29-2013, 11:20 AM
As far as I know I am. The idle is now fine. I unplugged my coils one by one the other day and the idle changed each time I unplugged them. I want to pull the plugs tonight to get a good look at them. The car will rev great at idle to as high as I want. But when it is under load it is like shit. I am going to run ohms meter on the coils tonight as well. But my guess would have to be timing. the exhaust cam is about 1/3 tooth retarded.

whereda40at
10-29-2013, 11:20 AM
I'll see about getting some pics tonight and post more tomorrow. I don't have internet in my new house and my work computer is very restricted.

rwtf
10-29-2013, 12:07 PM
boost/vac leak?

rwtf
10-29-2013, 12:10 PM
also it doesnt sound like you're running on all six. comp test it.

whereda40at
10-29-2013, 01:05 PM
boost/vac leak?
I have searched over and over for a leak and have found nothing.

also it doesnt sound like you're running on all six. comp test it.
A compression test was done on the car before I got it and everything was fine.

The car will drive fine until I try to boost it.

singlecamslam
10-29-2013, 05:05 PM
Definately sounds like a leak, how are you testing for leaks? It could be somewhere hidden.

Joedrt
10-29-2013, 06:39 PM
Smoke test it for boost vac leaks that happens to mine regularly either that or a bad plug/coil

BoredEE
10-29-2013, 07:48 PM
Do you have a boost gauge?

What PSI are you hitting, are you getting boost creep?

ultimateirving
10-29-2013, 08:08 PM
Also aren't Rb coils notorious for being piles of shit? I know my sr coil crapped out on me and while it would function well enough to drive every time I got into boost it would take a shit and break up

Sileighty_85
10-29-2013, 08:24 PM
what are the plugs gaped to?

whereda40at
10-30-2013, 09:47 AM
Definately sounds like a leak, how are you testing for leaks? It could be somewhere hidden.
I followed every vac line, boost line and looked at all gaskets(intake mani, exhaust mani, ect...) nothing was found wrong.

Smoke test it for boost vac leaks that happens to mine regularly either that or a bad plug/coil
I am leaning towards coils or plugs, they are on my radar.

Do you have a boost gauge?

What PSI are you hitting, are you getting boost creep?
I have a greddy ebc profec-1 boost is set for 12psi on high and 7 on low. boost will hit maybe 5.8 psi but still has zero power
Also aren't Rb coils notorious for being piles of shit? I know my sr coil crapped out on me and while it would function well enough to drive every time I got into boost it would take a shit and break up
I am going to research what coils I should switch to if that is the issue. It happened in my old sr and would break up after I was in boost but this is breaking up any rpm that I give it more than 10% throttle
what are the plugs gaped to?
I haven't measured them yet. I had pulled them out before and they were all pretty new.

Joedrt
10-30-2013, 10:48 PM
Splitfire are good but I would use the gm truck coils

Sileighty_85
10-30-2013, 11:58 PM
you need to gap them to .028. they are not pregapped from then manufacturer.

OnTheChip
10-31-2013, 08:28 AM
Could be a bad injector. The only time it sounds right is in overrun when the injectors are cut off anyway.

whereda40at
10-31-2013, 11:13 AM
I didn't get a chance to look at it this week. I hope to get a chance this weekend.

bardabe
10-31-2013, 08:44 PM
car is absolutely not on 6 cylinders, start there. OHM test the injectors and coil packs, do a compression and Leakdown test. if all of those pass ok, theck your ignition coil grounds and spark plug gap. followed by making sure all injectors are clicking open, once you've done all or before you finish doing all that you'll find your issues

-Juan

whereda40at
11-04-2013, 12:16 PM
the OHM readings should be....1.7? I Know plugs should be .028

whereda40at
11-13-2013, 07:43 AM
you need to gap them to .028. they are not pregapped from then manufacturer.

I took out the plugs. In doing so, I found a plastic disc in cyl 3 in between the coil pack and head. Then found a bunch of rust dust on the coil rubber at the bottom. Then once pulling all the plugs out, I found that they were all either .044 or .043. I gapped them all down to .028.

Could be a bad injector. The only time it sounds right is in overrun when the injectors are cut off anyway.
I am not sure now after getting this far.

I have posted pics to show findings as well.







So where I stand is now....

Car for sure drives better.
idle is good
at idle, some times the car will start running super rich and lots of black smoke comes out of the exhaust
The car reacts now to the different boost settings on the greedy profec e-01, the boost is very inconsistent right now. But the boost has never been set properly with the car running good. I am going to set it back down to basic.
At one boost setting, the car would be pretty much jumping but on hi boost and off, it would just seem like it has a major lag and never hits boost.
Boost will read 7-15 psi while fluctuating that much. Before it would read at most 5.2 and stay.
Questions
How do I check the OHMs on the injectors and coils? With the car running, on, acc, or completely off?
Where do I put the pos and neg on the coil?
What are you boost settings if you are running a basic bolt on rb on a greddy controller?
Any tips or tricks with the greddy e-01? I always used a world technology pbc-1. (which I cry every night I don't have it)
I don't have a cell light on, but can I plug up a scanner and maybe find a issue?
Thanks in advance for everyones help. Still open to suggestions. I currently do not have my air compressor hooked up so I can not do any testing that requires that.

JohnnyDrfiter22
11-13-2013, 08:12 AM
Maybe dumb but from what iv heard about RB's you will need atleast 4 grounds off the block and 3-4 off the head. I know the Aussie guys swear by this and a friend of mine has a rb25 says the same.

whereda40at
12-18-2013, 08:15 AM
I hate to be that guy that doesn't report back and just leave a dead end for people who search....

So after doing all of my searching over and over and testing and talking with RB experts. The issue was ignition timing. The mechanical timing is spot on. When I tried setting the ignition timing before with a buddy of mine, we went off of the white wire and not doing the spark plug wire in the middle. Also, we didn't unplug the tps brown plug when adjusting the cas. The main lead to figuring out it was the ign timing was the car would not make power when boosting and the vac at idle was only -2.4. I warmed the car up and had my wife watch the vac as I adjusted the cas. I haven't hit it with a timing light yet to get it perfect but the car now boost great and drives normal.

Thanks everyone for your input and suggestions. I will have a video up on youtube later. Subscribe to me by following the video link at the top of the page.