sr20det notch top troubles

[DCmonkey]

hello zilvia

Im hoping one of the sr20 guru's here can shine some light on my situation. i posted about this same issue on another forum, but havent gotten any love yet.

pickup up a 97 hardbody with an SR that was in it, which turned out to be shot. salvaged the head and had it refreshed and rebuilt then i sourced out another shortblock.

purchased a wiring specialties harness to wire it up since the prev owner had a crazy hack job of a harness.

After the usual turbo car hiccups trying to get it running right (vac leaks, ect ect.) i got her to turn on and idle somewhat decent. The problem now is that shes only pulling -18HG of vac when i know she should be in the 20's and after shes idled a bit the rpms drop and runs rough(unknown rpms due to the cluster needing to be wired to the harness) she basically struggles to stay on. she smells SUPER rich and worse of all when i try to drive she has almost no power, but the turbo sounds as if im supposed to be hauling A$$.

no colored smoke or signs of internal issues, just strong unburned gas smell!!

i am still in the finishing process of this project so a few things still need to be addressed like the gauge cluster and exhaust, but im about fed up with this truck because i cant seem to figure it out.

Changed-
CAS
Plugs .28 gapped
MAF(other one had a huge crack on the sensor)
CTS(she was flooding herself. replaced it and let it run to the point where it would normally flood.... this is where i am currently hitting a brick wall)

its a bone stock setup so the margin for errors i hope are a bit smaller, but this truck is honestly kicking my ass.

T25 turbo
370cc inj
isis turbo elbow
wiring specialties universal Pro-harness
WE ecu- stock according to prev owner

ive spoken to yury and his crew a few times. yury INSISTS to rule out the ECU and Harness which only leaves the possibility for either sensor or mechanical failure.....???

ive checked the timing and everything seems as it should. CAS was stabbed in with the valve cover removed to avoid stabbing it in wrong.

im so frustrated with this build that im not thinking right, so i hope someone can point me in the right direction.

got fuel, got spark, WHAT AM I NOT SEEING HERE??????

this is my first nissan so i have A LOT to learn


SOMEONE PLEASE HELP!!

[Kingtal0n]

probably ignition timing is wrong. First thing I would fix. The pickup is directional- go back and try it both ways, the cas should be pretty centered.

If not the timing then you need a wideband reading, next easy step.

[DCmonkey]

probably ignition timing is wrong. First thing I would fix. The pickup is directional- go back and try it both ways, the cas should be pretty centered.

If not the timing then you need a wideband reading, next easy step.

im not understanding what you mean about the pickup being directional?

care to clarify please?????

[DCmonkey]

spent some time working on the truck today and managed find and address a few things like the knock sensor only had one wire that was attached so i finally grew a pair and used the supplied subharness from wire specialties, took the valve cover off to make sure timing was set and it was dead on, CAS was actually a bit off center so i centered it. started her up after everything and it ran great. -20HG dead on so i ran it till she would normally start bogging and stuttering and low and behold she did it again, but this time i had my brothers helping me do some wrenching and luckily my younger brother discovered a drip from the gas tank which turn out to be a pretty decent leak coming from the sending unit which explained why the engine was constantly trying to recover idle. so i pulled the plugs anyway to see if she was flooding and all 4 were nice and ashy for a change as opposed to all blacked out which is good news.

ordered a new fuel pump and sending unit all together and a new OEM O-ring for it.......i already have a fresh set of plugs and 300zx TT fuel filter, so when the new sending unit comes in ill throw it all in together and see what happens.

i think the culprit now is a shot fuel pump/sending unit because prior to what seems like the fuel system loosing pressure, it was running great.


one step closer i guess.

[Kingtal0n]

great to hear about the timing, and yes as I have already mentioned your next step will be fuel related, would be great to see it leaning out on the wideband to confirm the fuel pump.

[DCmonkey]

great to hear about the timing, and yes as I have already mentioned your next step will be fuel related, would be great to see it leaning out on the wideband to confirm the fuel pump.

thanks dude:hsdance:the way she was spraying out i dont think will require a wideband to confirm. definitely big enough to loose enough pressure in the fuel system to affect the performance one way or another and oddly enough today the fuel pump sounded off when i first heard it prime. i dont remember exactly but i think the pump inside it now is a 255 walbro which it HAS to be by how loud it is or the pump was shot all along,but never leaked gas because the engine was running shitty.

[ultimateirving]

Vacuum around -18 is about normal. Maybe up to -20hg, the way you described it when the engine started to bog was after she is warmed up? Verify cts wiring and maybe look into replacing if you get nowhere with the other suggestions

[DCmonkey]

Vacuum around -18 is about normal. Maybe up to -20hg, the way you described it when the engine started to bog was after she is warmed up? Verify cts wiring and maybe look into replacing if you get nowhere with the other suggestions

Wiring to the sensor was tested for power and is good, sensor is new. Also notice my igniter chip was getting awfully warm/hot after I briefly ran it?? Wtf. For now I am going to focus on the new fuel pump and sending unit. The metal feed line from the sending unit cracked right on the elbow SMH.

and the saga continues!

[ultimateirving]

Wiring to the sensor was tested for power and is good, sensor is new. Also notice my igniter chip was getting awfully warm/hot after I briefly ran it?? Wtf. For now I am going to focus on the new fuel pump and sending unit. The metal feed line from the sending unit cracked right on the elbow SMH.

and the saga continues!

Heat on ignitor might be normal but if it's getting extremely hot that might indicate resistance or a short Somewhere. Possibly check your engine and ecu grounds as well

[DCmonkey]

Ok cool, that's good to know.

Today I got back into it, JB welded the sending unit for now, fixed a little coolant leak caused by a slightly loos AN line then topped off on coolant and let her run again..... Ran perfect for about 5-10 mins and then it started doing the same thing I,e, dropping idle real low and misfiring:(. Even so I took her for a quick drive down the road and everything aside she feels good (never had this engine running right since it was put together) but I know she capable of running GREAT, feels like it's down on power but she revs freely and even managed to see 7lbs for the first time ever. At stops she obviously feels like it's gonna die and I'm too chicken to let it go and see what happens since I'm in public roads. It doesn't die but sounds like idle is close to 500ish.for the hell of it I unplugged the TPS and revs went up high again as soon as I did,plugged it back and and back to burble burble burble then she tries to recover idle and then back to burbling, but atleast she's not doing the trademark IACV constant idle surge..........any thoughts??

[ultimateirving]

A couole things I would do. First of all wire in your consult port, clip a consult connector from a compatible vehicle in the Junkyard. It's a small trouble but worth it for future diagnostics.
After you wore that in, get the care to timing mode by either using conzult or the rev trick. Which seems to be hit or miss for most people. If it is idling in the correct range 850-900 rpm you can go ahead and move on. While its idling unplug a coil pack one at s time and see if idle gets worse. This is just to see if you have any dead cylinders. Cuz it does sound like a bad misfire.

See if that helps at all

[DCmonkey]

Gents

After a brief conversation with yury again I went and tackled the iacv again. Tried before but the plastic screw wouldn't give so I played nice and left it alone. Went back, sprayed it with a light coat of PB blaster and waited a few. Broke it loose and took it all the way out and WALAH!! Caked up to hell. Cleaned it out at bit and put it back in as yury instructed (apprx halfway between open and closed with the tps unplugged) put the battery back in, started her and and bam!! Running like a champ!!

moral of the story is, kids CLEAN THE DAMN IACV, especially after a rebuild.


She's been running good, now just some more finishing work .... Pics and vids will be coming soon...... Now in itching for a t28

[DCmonkey]

Here you guys go
https://youtu.be/V6VQg-c07U0

Now I need and exhaust and rad fan and done!!

[TurboTiger]

Glad to hear you figured it out. I've always thought an SR hardbody would make a great truck.

[DCmonkey]

Thanks dude,I can't wait to get it on the road. Thank you everyone who came help me out!!