did a boost leak test

[Needsoles]

ok so i did a boost leak test on my car. no boost leaks anywhere. I thought it had a boost leak. my car will start to jerk if i floor my car it it does this around 3500 rpms. but i can give my car a little bit over 3/4's throttle and my car wont jerk or anything and i can take my car to 7k no problem. so what can be causing my car to jerk and loose power?

 

[pj91gsx]

Did you use a use a boost gauge and soapy water? How many lbs could you get in the intercooler system? I put 25 lbs in when I do my test. It should hold boost for about 10 seconds.

 

[1gDSM4g63]

Check spark plugs and it could be your TPS sensors.

 

[Needsoles]

how do i check my tps

 

[ROOKIE1]

TPS Adjustment

 

[pj91gsx]

http://www.vfaq.com/index-main.html

 

[crimsondragon]

Make sure you did the test right.

1. Disable your mbc.

2. Turn your motor to 30* ATDC to avoid valve overlap.

3. Start your test at the TB elbow and focus on area behind the TB first.

4. Spray soapy water at TB gasket, BISS, TB shaft on both sides, IM gasket, injector insulators, brake booster, afpr and all vacuum lines/connections.

5. Open your oil cap and listen for leaks. (PCV, valve seals/guide, rings)

5. Listen to your tailpipe for leaks. (EGR, valve overlap, jumped timing, bent/unseated valves)

6. Once all leaks are fixed, move the tester back to the turbo inlet.

7. Spray down the compressor cover (known leak), BOV return/flange (DO NOT TAP YOUR BOV LINE FOR YOUR MBC!!!), IC end tank/fins and all connections. Re- test.

8. Note that you will leak air into the crankcase through the turbo seal but do not panic, this is normal during a static pressure test as long as there are no shaft play.

The desired test result from the begining of the LICP (bypassing turbo) is around 20psi (on boost gauge) with the compressor set at 30psi, while taking no less than 30 seconds to bleed down to 0.

As a reference, my last test on my 500 mile new engine, I was able to pressurize the system to 25psi, bled down to about 16psi (my 1G bov) in about 30seconds, then took about 3 mins to 6psi and just kinda lingered there for a while. It's not easy to do but the point is it's possible. My next goal is 30psi After motor break in and Dodge modding my BOV. A boost leak test is one of most pita but important regular maintenace task, the key is patience and endurance, have fun.

 

[GST with PSI]

Check spark plugs and it could be your TPS sensors.

Spark plugs. Try a new set of NGK BPR6ES especially if you aren't already running them. That's where I'd start if you didn't already. Also check out this:

http://www.vfaq.com/index-main.html

Not sure what plug wires you are running but no plug wire is exempt. Make sure nothing in the article above applies to you.