CA seems to rev slowly

[xyster]

I've had a CA in for a while, and it always seemed to rev pretty slowly, but I haven't been able to touch it in 8+ months (iraq deployment). I've spent the past week or so trying to get it to run better. Alright, here goes:

-Stock swap, plus Greddy VSPL FMIC, HT hot pipe, Blitz SS Bov, Walbro 255, Infiniti J30 VLSD (in case it's a gearing issue), Spec Stage 1 clutch, Autometer mechanical Water temp/boost/oil pressure, Apexi SAFC II, HKS turbo timer, pdm racing catch can - plumbed per thread on SXOC.

-Stock boost, which with the fmic peaks to about 10 on the gauge as read from the vac port in the intake plenum right behind the TB

-It idles smooth, 800-870ish, idle tuned per FSM

-Timing 15 BTDC, set with cut plug wire on first coil method, done twice

-Water temp as measured at upper rad hose is about 175-200, depending on ambient and driving style

-ECU is throwing only code 55 in Mode 3, and seems to be blinking a proper mixture in modes 1 and 2, which leads me to believe the lambda is good (correct me if I'm wrong)

-Today, I got out the FSM: reset the idle, checked the resistance on TPS, idle switch, various idle-related valves, injectors, ecu coolant temp sensor (newly replaced)

-Checked all the clamps and connectors on the fmic piping...can't feel/see/hear any leaks...I intend to pump it up with my compressor as soon as I can find the right size cap for the turbo inlet. Boost seems stable while driving.

-I got no continuity across any pins on the TPS, with the throttle open or closed. I assume this means it's bad. Could this be causing the problem?Edit: Lemme clarify here: By TPS, I mean the actual TPS part of the throttle body sensor...the one that has a small "pigtail" cable with a brownish plug on the end...not the actual square black box with the plug molded in. The FSM leads me to believe the molded plug is for the "idle switch" and the pigtail is for the throttle position sensor.

-Little to no oil in FMIC piping, turbo spins freely with little to no play, axial or radial.

-I replaced all the gaskets between the head and the downpipe less than 1000 miles ago, and put lockwashers on all the bolts. All are still tight.

-Edit: New plugs, all of which still look new. All the coils are good (checked continuity, and did the "pull a coil and see if the idle changes" thing).

-Edit Again: Alternator charges fine, battery is relatively new, redid all the grounds today, turbo timer reads 14+ volts.

i'm at a loss here...it seems like I've checked everything. Does the CA just really rev this slow? It feels like my vg33e Frontier revs faster, even in high rpm. I added the blitz bov today, and it seems slightly more responsive...but still. Maybe I'll make/post a vid of it running in a day or so.
Modified by xyster at 5:32 PM 3/30/2005

[pulsar gtr]

The CA revs FAST man, you definitely have a problem, if the ecu is giving Code 55, which is no fault found, this means that the tps is good.

You are definitely on the right track with your trouble shooting method.couple things to inspect. as the car running, look at the secondary buttery fly valve which is right next to the fpr, rev the car a bit at ideal and you should see the valve shaft moving up and down, if it doesn't check the vaccum that controls it.If this is not hooked up, it can cause a bit slow reving.

Also do a compression/l eak down test and see if the engine has a low compression.

Good luck,PULSAR GTRRafi

[xyster]

I imagine you're probably right about the TPS, but just to eliminate it as a possibility, what US motor can I get a replacement off?

[ca18detizzle]

yeah, i would do a leakdown and comp test.

[xyster]

Should have mentioned to begin with, did a compression test maybe just a couple hundred miles ago. I don't remember the exact numbers, but it was within spec, though pistons 3 and 4 were a near thing.

I'll do one tomorrow again, just in case, and post the numbers.

I'm also checking the fuel pressure, butterflies, and a fmic pressure test if I can find a decent cap for the turbo inlet.

I'm on leave...so I can devote entire days to this...heh

[crazymax]

Have you tried yelling VTEC!!! when on the throttle???LOL, jkGood luck..

[f s t caz]

i never really thought my CA reved all that well either. it seemed very slow to rev when i blipped the throttle, compared to the 97 maxima i was also driving at the time. I had great compression #'s too. I always attributed it to the uber restrictive o2 sensor housing/full stock exhaust choking up the turbo. maybe one day i'll put things back together with the right parts and not have the problem anymore.

[float_6969]

I've got 2 extra TPS sensors that I know are good and work well. I'll sell you one for cheap. My email is [email protected]

[cadet]

mine revs slow due to the fact that a boost leak causes it to run like poop... might want to check that.

[xyster]

Just did a compression check:

1 1552 120 140 w/ capful of oil added3 1454 150

Looks like the rings on 2 are bad.

[cadet]

sure sounds that way...

[droopy_map]

Dont want to sound naive, but arent the exact compression values supposed to be at 170? So what if he gets 155 or there about, is that acceptable?

[xyster]

FSM says 171 standard, 142 minimum, and 14 max differential between cylinders.

That 171 is for a brand new motor that's at full operating temp. 155 is perfectly acceptable.

[jjwilks240]

it revs slow compared to my ka untill i hit boost, then once it hits game on.

try and find someone else in the area with a simialr setup to you and ask if he can drive you around or even if you can take a quick boot in the drivers seat.

[cadet]

mine is doing the same sort of thing, occasional sputtering as well, I don't know... need to check for codes

[Notchbackca]

keep in mind you have a 30lb flywheel...