Hey guys I will try and make it as short as possible.
94z28 heads,cam,edel intake, scorpion 1.6 RR,58mmtb,cai,longtunes,xpipe, fuel pumpbooster(not the one that goes hooked up to the TPS), stainless steel fuel line relocation wrapped with DEI reflective wrap not the tape
New parts- ac delco ICM and coil ( I put thermal compound behind the sensor plus I have the whole icm and coil which is also new about 3inches off the head to avoid overheating)
all ground engine to chassis grounds are new and using 2 gauge

so what happens?
After driving for a while id say about an hour the car suddenly stumbles and dies. Wait 5- mins and starts up stumbling then rpms jump up and runs normal then does it again about 15 mins after.
Also if I hit a bump hard enough the car stumbles and dies put it in neutral while the car is rolling and starts right up perfect.
another issues is car runs rough under very very light throttle mostly during start up and warming up?

Ideas?

 

Have you scanned it for codes?

Describe the fuel pump "booster".... is it a voltage booster for the in-tank pump, like the Kenne Bell "boost-a-pump", or an inline booster pump?

Describe the "stainless steel fuel line relocation".... is this a replacement and relocation of the stock nylon lines with braided S/S lines? With the addition of the DEI wrap, are you concerned because the lines are too close to the exhaust?

 

Ignition switch ?? Ground to Pcm ?? idle control valve ?? Fuel pump ???
Just guessing .....

 

sorry forgot to mention- no codes at all not even when it stumbles or dies
the fuel pump booster has a wire that goes from the alt to a pigtail that connects to the plug on the rear seat and then the factory plug goes into a new from from this sysem it has its own relay ( this system is the same as the racetronix)- i have had the shuting off problem for a while and it does it with this system disconencted as well so i know its not the system)
Fuel pump is only one year old as well as the fuel pump relay under the driver side dash
fuel line relocation is the same as speed inc that they have you run it next to the brake lines ( these probelms have happen before the relocation)
how could the igntion switch play a part in this?
my grounds are good and tight but ill recheck tomm (maybe thats the stumble when i hit a hard bump even though it doesnt always happen) but 99% sure the ground are nice and tight
maybe the IACV
fuel pump is new

 

Did you make a trap door for the fuel? If so it would be worth pulling the pump back up and inspecting. Also the floats on the fuel pumps are real touchy so may not give exact reading so if its a little low on gas(below 1/4 tank) try adding more. As you stated all grounds seem to be well connected. Seems I've had these problems before and the fuel pump always was my problem. (Seal not fully sealed, internal fuel pump hose disconnected. Also a faulty fuel pump? Hope these things help.

Sent from my Z796C using Tapatalk

 

Yea i did the trap door ill check it out, it has a walbro 255 pump about a year old.

 

and it happens no matter how much fuel is in filled up or low.

 

A lose wire in the switch ..... could shut the engine off while driving the car
it happened on my truck..... manual transmission.... If I would hit a bump hard the truck would
cut off then restart by itself and backfire really loud... I could bang on the wheel and the truck would cut off like I turned the key
Pontiac G5 and the cobalt has a recall on the 2005?? ignition switch in some cases the car would not re start for a few minutes

 

I hate to say it... because I am the biggest advocate of the opti. But time tondig in and check the opti. My money (only because of a recent opti failure with similar symptoms).

LTXtech.com is my drug.

 

Ill try hitting the steering wheel abit around the ignition area and wiggles the wires and check pigtails are snug.
yea thats my other idea the -opti but hoping not lol its only 2-3 years old idk if thats what they normally last i did put RTV sealeant all around it like everyone says. not to open up a can of worms here but the one i bpaught was a BWD-- should i spend the money on an MSD or AC Delco one or i should be good with the BWD which has ran great since i got it untill now if the opti turns out to be the problem

 

or can i get a way with the MSD cap and rotor kit? and correction i didnt buy the bwd i got the delphi one

 

Problems with the optical cam position sensor would set codes. The key code DTC 16 for the loss of low resolution pulse signal. That will shut down the engine, and does NOT turn on the SES light. I don't think I've ever heard of an Opti shutting down the engine from hitting a bump though.

 

So im guessing its the opti now the other question I have is brands?
I would assume msd has better internal parts for higher performance.
could I get away with other regular brands as long as I seal it up good with rtv? I do plan on buying the msd if it performs better but later on like in a year or more when I do a 355 build. Msd is like 450 I can get a regular one from advance for about 100 with my discount.

 

But you indicated you have no codes..... why are you guessing it's the Opti?

 

Sorry I understood wrong ur previous post... so then your saying its not the opti?