lennox

I'm having a problem that I can't seem to get around.
My car has been jerking violently sometimes in 1st gear, most of the time in 2nd, and occationally in 3rd, sometimes around 5000rpm @ 0.6 bar in 1st or 2nd, other times as low as 3000rpm, boost only around 0.3 bar in 2nd. If I increase boost, jerking is more violent. I am currently running wastegate pressure with 95 octane fuel. It feels and sounds as though a boost pipe has come off, but all is in tact. If I drive at half trottle, no problem, but if I apply full throttle, it jerks. Suprisingly everything is fine in 4th & 5th.

Recent Mods since this has occured:
Rev Hard T3 manifold
Precision 5557E Turbo
Piping to suite new setup

Factors already eliminated:
Tried MBC instead of EBC
Replaced Spark Plugs
Disconnected Cooling mist
Replaced Cam position sensor
Changed map to Base map & 6 months ago map
Replaced Dump Valve
Reconed Wastegate
Checked boost pipes
Replace clamps to t-bolt clamps
Swopped relays

All other Mods:
HKS Cams
K&N Induction
720cc Greddy Injectors
3" OBX exhaust & Downpipe
Greddy Profec B II Boost Controller
Xcell External Wastegate
RevHard T3 Manifold
Precision 5557E Turbo
TRE Performance Fuel Pump.

Please help!

Clutchdc5

iTrader: (1)

I vote piping u didn't check

lennox

piping? You mean like a crack or something?

detroit pistins

iTrader: (102)

do a boost leak test and see if there are any major leaks.

lennox

If it it a boost leak, how come 4th and 5th has no problem? I can push 4th from 3000rpm till red line with no problem.

lennox

We are getting somewhere finally! We removed the dual map that I was running and install a single basemap, it popped a engine light which brings up P0340 error, Camshaft Position Sensor Circuit Malfunction. I don't know how come the dual map didn't want to pick up this error. I'm going to change the sensor and see if it sorts the problem.

lennox

I tried replacing the Camshaft position sensor but the problem is still there. Any other suggestions?

lennox

Guess what, it was a boost leak. Problem Sorted. Thanks