Fuel cut with codes 34 & 35

wamorgan88

New member
So I've been battling an issue with what I believe to be the fuel cut. 1st gear cold start will boost ok. After that max boost 2 psi then falls on its face. Replaced the map sensor ( which was wildly expensive) and no change. Scratching my head at this point. Would a boost leak cause this and if so would it be within the boost track or exhaust side? Thinking about deleting the stock boost controller and seeing if I have an issue with that that will not code. Any ideas or direction would be greatly appreciated.
 

wamorgan88

New member
First gear 15psi. All others 2psi. Also the check engine light doesn't stay on. Just when it's hits the 2 psi of boost.
 

wamorgan88

New member
I think it has to be boost creep. The gauge specs are above, 19in/hg at idle, 15psi top of first, 2psi max with any other gear. Engine specs are .020 over pistons, ported and polished head. Stock valve train, stock turbo and manifolds.
 

wamorgan88

New member
I did check the waste gate operation, at least to see if it was stuck, its not. Ive just recently bought the car and i do know the engine has just recently been overhauled. Ive already found multiple oops spots where either grounds weren't hooked up or wires were broke off or not connected. What i think may be a possibility is the vacuum lines for the stock boost controller are not properly routed. i cannot however find decent routing diagrams. I also found a cracked coupler between the intercooler and throttle body. It will be in tomorrow. As far as the boost level at 15psi, im baffled. It will only do that once per drive cycle, and it has to be in first, so i can never catch it.
 

wamorgan88

New member
So got the new coupler in, went for a test drive and made a couple of discoveries and one hell of a story. So the codes will not throw as long as the boost level stays within stock range, which tells me there is a waste gate issue and not a sensor issue. The codes will pop at over boost levels only. Well as the test drive continues I decide to keep driving around checking out any other issues. I keep going and I notice the stock boost gauge zeros out but the aftermarket one is still working. I also notice it no longer hits fuel cut and will boost, and boost and boost, all the way to 20 psi. I then start noticing noises and smells. It dies and I pull over and pop the hood. Throttle cable is on fire, and fell down onto the turbo. Waste gate hose has popped off, causing the over boost. It's overheating and barely runs. I get it home and now no boost gauges are working. Both hoses blew off for the gauges, and it blew the coupler out from the turbo to intercooler. So now I gotta start looking for waste gate issues, couplers and throttle cables lol.
 
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