Starting problem please help!

[Forbiddenknight]

97 gst
7 bolt
Ingen intake
16g with tubbed manifold
Greddy bov
255 intake
Eagle rods wiseco pistons 8:1

The car struggles to start you have to crank it and if it doesn't start in the first few seconds you have to retry because constant cranking won't get it to fire. Once it fires it'll idle fine won't jump spike or idle high or low.

Once you try to throttle it it'll die instantly or choke out. But you can play with it enough by repeatedly pushing the gas fast every so often get it to idle high to build boost at that point it'll Rev up fine if you don't let it drop down below (2000 rpms)

It's got new spark plugs (am running rich based off last plugs)
I don't think that's related but will ask how to fix that too.

I bought a new tps sensor put it on and think I set it right because I got the car to an idle point again.

The vacuum lines have been plugged for boost controller. I'm open to all opinions and will tell you all when it's fixed.

 

[Yoshi4250]

Have you checked for a boost leak

 

[lasershark]

Any CEL's codes?
A quick check, make sure the maf didn't come loose/lose connection.

Need a little more info, was the car sitting for a while?
when did the problem first occur?
Any recent repairs or upgrades?

 

[SasaniFab]

Start at the beginning. Compression is good? Leak down test performed? Your getting fuel and spark? Check base timing. Ecu is in good shape with all grounds in place.?

 

[Bo0sTeD 4G63]

Check for any boost leaks and make sure your MAF is good and plugged in.

 

[boostdawd]

Sounds like it's getting too much fuel. Does it matter if the car is warmed up or not? When it does start and you drive it around and stop, if you try starting it agaim does it start? Things to check. Coolant temp sensor. Fuel pressure regulator. Caps on the ecu itself. Just a few things to cross off the list.

 

[eSpyder407]

You said these are new plugs... Chance the wires are in the wrong order?
Coil pack - 4-1-2-3
Valve cover - 4-3-2-1-timing belt

 

[Forbiddenknight]

Engine was just rebuilt car has about 10miles on it. I'm not leaking boost. No cel codes. Eagle rods wiseco 8:1 pistons. I thought was lack of fuel just upgraded pump to a kenmor 455 lph with an aem regulator all of that is fine. Injectors are good. So I tried spark new 10.5 mm wires with new OEM coils. Plugs themselves are gapped perfect. Timing is perfect. New ECU.

It doesn't matter whether car is warm or not it acts the same. I can play with the throttle enough going wot then nothing back and forth fast and eventually get it to rev up build boost and purge. If I can play with it and get it to move fast enough to get the car rolling decent. Probably unhealthy but I can drive the car and once past 2500 rpms it's fine to drive. However this might be what solves the problem to one of you. Once around 3500/4k rpms on 3rd or 4th gear the car will start to backfire and shoot flames out the exhaust the car doesn't build the boost it should even though it's sealed ( I believe because the back fire. The maf has been piggy backed once before but I re spliced everything to new and sodered the ends to ensure a good connection. I have 2 mafs for the car and nethier one makes a difference so I'm assuming that's not the problem?

I took my boost controller out and trying to bring what I can back to stock to try to get it running again then proceed from there.
I've had about 15/16 dsms and none has ever done this. I would take it to a mechanic but all refuse it because it's modded to much. They can't even diagnose it so I can fix it

 

[lasershark]

because it's modded to much.

You should create a profile so we all can see what you have as far as mods go. It can only help...

 

[pauleyman]

Did it run right before the new motor? what did you change? new or different injectors? different tuning etc