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Any ideas???

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Old Dec 17, 2012 | 06:57 PM
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Default Any ideas???

Here are my issues im having since the cam swap. Engine hard to start when hot, misses at idle speeds, misses throughout driving speed range, lacks power. When it is warm and I need to restart I haft to give it 1/4 throttle to run then feather it for a min to stable out... this is what im experiencing a rough engine idle, a misfiring engine, or an engine that hesitates or stumbles when attempting to accelerate...I have changed spark plugs, plug wires, injectors, coil pack, intake gasket to the MS98016T, changed all exhaust gaskets, new vacuum hoses, changed bank 1 O2 sensor, I've had a crankshaft relearn, compression test also... Fuel pressure is at 50psi and 60psi at start up. At WOT I have 60psi.
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Old Dec 17, 2012 | 07:02 PM
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So.....I assume you had the pcm tuned for the cam after the swap?
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Old Dec 17, 2012 | 07:06 PM
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Yes mailed PCM/TMC to TSP. They sent everything to me after they were done with "Tune"
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Old Dec 17, 2012 | 07:08 PM
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You have identified the problem there.
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Old Dec 17, 2012 | 07:13 PM
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LOL the Tune ?? If it is Im NOT going to very happy..
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Old Dec 17, 2012 | 07:20 PM
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Yep, stinks like bad tune.
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Old Dec 17, 2012 | 07:30 PM
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Damm it I even paid for the dyno tune!! drove to Lubbock! and it was still the same. But had a Valve "float" on the dyno so we stopped. And on the way home some of my outer valve springs broke. But fixed all that. Still runs like a big I sent TSP email today and nothing yet..
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Old Dec 17, 2012 | 07:44 PM
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Ok, that is a vital bit of information you left out! If you had valve float, and broken valve springs there is a 99% chance that you have bent valves from open valve meeting piston.
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Old Dec 17, 2012 | 08:36 PM
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Left it out Cause I was having the issues before the dyno. Redone the heads valves are fine just had to change springs. and still having the same issue.
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Old Dec 17, 2012 | 11:05 PM
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Originally Posted by TexasGMC08
Damm it I even paid for the dyno tune!! drove to Lubbock! and it was still the same. But had a Valve "float" on the dyno so we stopped. And on the way home some of my outer valve springs broke. But fixed all that. Still runs like a big I sent TSP email today and nothing yet..
If there was issues to begin with, How can you expect TSP or any tuner for that matter to fix the issue???

Tuning does not fix mechanical issue's. If you have resolved all the mechanical issues, then get it tuned.

https://www.performancetrucks.net/fo...-issue-511293/

https://www.performancetrucks.net/fo...-510885/page2/
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