RADEoN

iTrader: (12)

I recently put H/C on my CTS-V (PRC Stage 2.5 and TSP MS3 237/242 112LSA), and the tune we did on it was pretty much to get me home. Well, the car acted sporadic and started throwing lean codes, so I called up PCMForLess, and had them send me a new, tuned to my specs PCM. I got the PCM installed, and it really ran great, except that the car would not idle... at all. I called them, and they told me to drill a 3/8ths hole in my throttle body, and the idle issue will be resolved. I did that, and absolutely nothing. I removed the line that goes to the valley cover, from the throttle body, and it ran, but the idle stayed high, so I replaced the line with a longer one (to ensure 100% there's not a kink), and the car started stalling immediately after i would start it, and I'd give it gas, and it would run, but it would always drop to 0 and shut off.

I currently have occasional check engine codes for:

Stock, quick tuned PCM: P0101 (Maf circuit) P0106 (MAP) (both replaced), Bank 1 and 2 lean.

PCMForLess PCM: P0101, P0106

with my stock PCM, the car idles, and with the PCMForLess, the car runs way better, but doesn't idle at all.

What can I do?

dodson55

iTrader: (18)

i think a 3/8 hole is way to big to drill in a tb myselb nut the problem is that your idle parameters need adjusted with a cam as big as that its hard for a mail order tune to do exactly what you want

RADEoN

iTrader: (12)

it wasn't 3/8ths my mistake it was 5/32nds

TransamGCS

iTrader: (2)

you should get a dyno tune a mail order tune for the mods that you did are only good just to get you around for a little bit and so you can drive to a tuner with out having to tow it. a good tuner that knows these engines should be able to fix it. but drilling the hole in the throttle body might make it a little harder for the tuner if it originally never had one, but maybe not

badazz81z28

iTrader: (6)

I know its too late, but why didnt you have TSP tune your PCM? Their Cam/head combo, I bet it would only need minor tweeks on the dyno if they did it.

Mzenon88

I recently talked to a rep from tsp in regards to the ms3 cam I told me great cam lots of r&d but that cam takes a tune that is right on the "money" according to the rep chances are you will have to tweak the afr and add or pull timing to get that cam to be livable dyno tune is the best in the case for sure

RADEoN

iTrader: (12)

Badazz, I had a dyno tuner lined up, but he keeps going up in price 75 bucks each time I talk to him. We're currently at 575 up from 425.

2doorfury

iTrader: (12)

575 is a little high in price..some of the best tuners around will tune ur car on the dyno for $500. looks like hes charging you for the dyno time too.

TransamGCS

iTrader: (2)

A dyno tune should run you around 400 to 500 for a tune using the MAF if you have a SD tune then that would be more like 600 range.

Badazz yeah you would think that tsp combo that tsp could get a good mail order tune, but not, i installed ms4 cam prc 215 heads had them do a mail order tune and what they gave me was a pretty safe rich tune which was good enough to get the car started ideal ok and drive it around but once i took it in for a dyno tune it was really tweaked nicely. with mail order tune their was alot of room for improvement just the dyno number alone with the tsp tune it was 380 rwhp after the dyno tune i was over 450 rwhp . so even with tsp i think its hit and miss how close they can get a mail order tune with a actual dyno tune

RADEoN

iTrader: (12)

i actually think i may have figured out the problem. my intake bolts were all very loose, loose to the degree that i was able to spray carb cleaner alongside where the intake touches the head, and it would get sucked in and rev weird... then i started tightening them down, and snapped one off. so now i gotta back it out and get another bolt.

crainholio

iTrader: (2)

You really need to get a torque wrench calibrated in inch-pounds, and tighten the bolts correctly using the 2-step GM process, or you're going to have problems.

RADEoN

iTrader: (12)

Well, I got the intake bolted back on, and the car started and idled awesome, no check engine lights, and it sounded awesome. Idled for around 10 minutes, so I cleaned up and took the car for a spin. It started off by running awesome, then my idle started getting higher and higher, and the car started stalling again. Then as I'd coast, my idle would slowly crawl up to like 2500 to 3000. I got rid of my ported throttle body (and put the coolant passthrough directly from the output into the radiator because I'm tired of losing coolant all over the road), and put the stocker back on. The car (with both throttle bodies, the stock one has the small hole in the plate, as recommended by PCMForLess, ported one is brand new, and doesn't). I'm still throwing the two check engine codes.

Are you guys thinking vacuum link, or still tune issue?