Suddenly Engine Dies after months of work

[99t3gst]

Hi Guys,

Sorry if long winded, but i wan'ted to be as descriptive as possible

My 99gst: t3 turbo, obx 347 stainless headers, tial 38mm wastegate, stock bov recirrculated, stock injectors, greddy sp2 2.5" catback exhaust, bomz racing intake, stock MAS

After months of work/ diagnostics to get the car running, which eventually happened after adjusting timing (was of by 90 degrees ), replacing practically everything ( water pump, CPS, Ignitor box, pulleys, plugs, TPS, right motor mount). (Lots of white smoke at first however, can had not been started in 6months. After warming up cleared and did not happen again. Was running fine pulling strong, not obused never over 4k rppm since first time driving it home.

Car made a pop sound at around 50mph in 5th gear, the tach started fluttering about even though pressure on th gas pedal was constant. Car's back firing, wont idle without giving gas. Will still start however will not run correctly. Any ideas?

My thought is bent valves due to timing being off so much, however i've been told it could be crank walk.
The car has 55,556 original miles so maybe to early for that, however evidence that previous owner was spraying nitrous.

Any thoughts would be GREATLY appreciated

 

[reeper]

2 things to try.
Compression test http://www.dsmgrrrl.com/FAQs/compression.htm
Boost leak test http://www.vfaq.com/mods/ICtester.html

 

[andymoraitis]

They also behave that way when you blow an intercooler pipe off. The car will POUR tons of smoke and hardly want to run since the MAS is having trouble metering fuel due to all of the lost air. Get under there and have a look, but also make sure you do a compression and boost leak test as recommended above if all of your IC pipes are on.

Good luck and keep us posted,

Andy

 

[99t3gst]

Sorry i forgot to mention, i only have the stock side mount intercooler for now, i have yet to put on my fount mount yet, i have it just not on. I will do the suggested tests and also check my couplings. thanks

Anything nfurther from anyone is still appreciated, The more minds the merrier

 

[99t3gst]

also the car didn't pour any smoke when the "pop" happened. It simply made the sound and then the fluttering of the tach (stock tach).

As i personally siad i think it maye be the valves.
If anyone knows of symptoms that happen with crank walk that i can check for that would also be helpful. but i'm praying thats not the case

 

[99t3gst]

to add more info, the car drove FINE for at least 5-7 miles, NO problems at all before the issue happened. Wastegate opening properly, making boost, accuratly responsive tach, no fluttering pulling stong, then pop, and now maimed.

 

[PieEyedPiper]

Like they said, boost leak testa nd compresison test and DO post back your numbers. Do a wet test too.

Also ditch that plastic BOV! while your car should run ok with it, it's a major failing point in the system.

 

[99t3gst]

I have a greddy type s bov, but i wasn't going to fab a pipe mount when my intercooler kit has one! I just needed to get it home to put the fmic on, but then my heart was torn drving it home with that lovely POOF! and dead.

 

[andymoraitis]

If you've indeed toasted the valves, a compression test will tell you right away. As mentioned above, that should definitely be your next step.

Let us know what the numbers look like,

Andy

 

[99t3gst]

will have to wait a lil while to do the test until the lovely funds come in, being broke sucks.

If so would you recommend a new head with changed seals or simply swapping the seals, lifters, rockers and such on my original head?

I know rebuilt would be the best way to go, yet $450 out of pocket right now isn't really an option.

 

[99t3gst]

update: all four spark plugs are fouled. Traces of oil in all cylinders. No boost leaks all pipe and couplings are tight. Will post compression number on thursday when i get the tester.

Thanks all

 

[Rush]

i had the same thing happen to me.i had 2 pops...almost sounded like pre detonation on mine? i drove a 400+mile trip afterwards and it drove flawless...at 75 id barely tap the gas and rocket to 90mph.dont think it was the valves.could be wrong. i also got a open loop,insuffient coolant temp code and a fuel trim bank 1 code before the pops...did you get any codes?

 

[99t3gst]

thanks everybody for all the info.

Have pulled my block and found i am a lovely victim of crankwalk (off bt .030)
I dont have the time nor money for a 6 bolt so a 55k 7bolt it is from my friends car who's already got a rebuilt 6bolt going in this weekend. thanks for all the help!