boost = NO torque

[Heyst]

If new, you can adjust TPS voltage when wrong. If TPS voltage is low on old TPS = TPS is stuffed. Replace TPS. I bet the surging will disappear when you change TPS.

is there an interchangeable part number?
I checked that list, but even the list should be updated.

if not, where should I order from?

[BurlyR32]

RB20's don't have torque, there's our problem. I'm experiencing the same thing :x

[Skym]

Heyst, replace TPS with a new TPS from Nissan. The stock TPS wears out the track on circuit board inside TPS and bends the idle, WOT pins at each end of track. They are non repairable and need to be replaced. Usually around the same time the o2 sensor needs to be replaced. Both are routine maintenance items, so not wasting your $$$. 02 sensor is replaced every 40,000-60,000km. TPS can fail at around every 30,000km or so (depends on how you drive the car). Sometimes TPS can last longer than 30,000km.

[WildCard_]

that tps reading is good.

You mentioned earlier your stock boost gauge says you have 0 vacuum at idle. Time for a vacuum leak test.

[Heyst]

at idle my boost gauge does show vacuum, it IS in the negatives. I'll take a picture, or maybe even a vid. but to best describe I'll try to draw a picture here.

- -7
-
- 0
-
`right about there
- -7


EDIT:
Picked up a vacuum test gauge. where exactly should I plug it into?

also, about to go clean my throttle body. its a little gunky inside. after I do that should I re-adjust my tps? or my idle screw?

EDIT EDIT:

Had a tech come over tonight, plugged in a diff ingniter and I still have the same issue. Now my overheating cat light likes to be bipolar. sometimes it blinks, sometimes it stays on for a second, and briefly will it stay off. clogged cat maybe? I'll check it out tomorrow.

Tech doesn't think its an ignition problem, maybe something stupid. We're going to try a different tps tomorrow, and different maf.

also put new gaskets on my TB and what maybe a wastegate? or stock bov on the J pipe. sits right on top of the motor, little tube on left side, big one on right.

my tps reads .489 - .5 at idle, and WOT reads 4.xxx volts maybe 5.xxx

[Heyst]

ok so tonight I swapped out the tps, then I swapped out the maf. both for good known working ones. still same issue.

as soon as the car builds pressure/boost the car will bog and jolt. the more load = longer the bog and more severe the jolt. If I shut the car off for a second and turn it back on then right off the get go it won't doo it.. for maybe 5 seconds then it'll start this process all over again.

currently have all the IC piping off again to inspect it.

could a clogged cat also be the cause?

[Skym]

Clogged cat would light up cat light on dash and I think engine ECU goes into limp mode (runs rich to bring down exhaust temps).

[WildCard_]

interesting about the cat light. did this happen before or did it JUST come on?

a partially clogged cat can cause restriction under load. If it was fully plugged the car would stall out under load.

I think it would be the other way around skym...a rich mixture is gonna have extra fuel in the cat being burned = higher temps.

[Heyst]

The light hasn't come back on yet. It would just blink random amounts / intervals.

going to pop out the cat today and see how bad it is. other than that I have the car over at the techs house, might be a boost leak? all pipes LOOK fine under inspection. might be time to build a boost pressure builder thinger

[Heyst]

solved

end tank on stock IC was leaking

thanks everyone

[Skym]

As far as I know it's a exhaust temp probe, so when cat clogs, exhaust gas collects in cat more and temps rise at that point in exhaust and sensor gets hot and triggers the cat light. Running rich drops engine and exhaust temps until you can reach a Nissan dealership. At least that's how I understand it.

[ferrero_rocher]

do u have a FMIC??
or SMIC?

[Heyst]

SMIC


weird thing, we swapped them out tonight and still same problem.. just not as bad. Might be a lose clamp or something we'll have to chase down tomorrow.