Car shaking/hesitating under boost 4k+

[Mistaspakles]

Under WOT the car will hesitate/shake over 4k. This happened to me before, and I replaced the plugs and wires and it was all good after that. Well, I replaced my plugs (NGK BPR7ES, gapped at .028) and wires (Accel Thundersports just last month (I do this every year), and now I'm experiencing the same problem. It can't be the plugs/wires since they are new can it? Any other ideas?

 

[meliketoball]

I bet you have a boost leak somewhere. Get that tester out and soapy water and begin to SPRAY! Not nitrous of course. keekee.

 

[Mistaspakles]

Umm...not really familiar with that test. What do I need, and how do I do it?

 

[cavillac]

search the tech forum.

 

[jeepzj94]

Yeah, I'm having a very similar problem. Boost leaks seem to be the primary cause in a lot of situations such as these. Also, a boost leak tester is very simple to make. Most if not all of the parts you need can be purchased at your local hardware store for less than $10.00. I lucked out and had everything I needed to make one already lying around the garage

 

[twoTSis]

Umm...not really familiar with that test. What do I need, and how do I do it?

Boost Leak Tester:

Boostpro.net : Guides - DSM - Instructions for Boost Leak Test

Printable version at the bottom of the site.

 

[gio_daredevil]

you should also check your vacum lines. my car did the same but i did a compression test, turns out i had messed up pistons rings on 1 piston oh and a cracked head :]

 

[grdsm]

best bet is to start with a boost leak test then move onto checking all of the vaccumn lines, maybe the turbo for any shaft play. does it ilde funny? does it only do this when in boost?

 

[mschlanglv]

Check your ignition timing as well. Severely retarded timing can cause surging under load.