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Here's the deal my car has been choosing not to start from time to time, it comes and goes like the wind so nailing down if it is no spark or no fuel has been challenging. I do know it has very good pressure at the fuel rail when it wont start (40psi). by the time I go to check for spark it always starts so it is very nerve racking. I scan it all the time and it has no codes pending or otherwise. I have made sure any fuses related to fuel injection or ignition are making good contact in both fuse panels. I have yet to test the relays but swapping them around hasn't exposed a bad one yet.

Today I had the same no start situation but this time after I got it started it ran like crap not a steady miss just really ruff until it would just die out, at the same time if I put it in gear or blip the throttle just a little bit it would die immediately. After about ten minutes of it doing this I finally got it to go into gear without stalling and drove it home. I had to push it fairly hard to keep it from stalling, thus I noticed no boost, the gauge would only go to zero. I verified what the gauge was saying via the aeroforce and indeed the MAP wouldn't go to a positive reading at WOT( I can definitely hear the supercharger and the belt is for sure on, but I don't feel the boost) On the other side vacuum isn't anywhere near what it should be either, it only reads -4psi on the gauge at idle. I removed and visually inspected all the vacuum fittings and tubes which all are fine.

I'm very aware that I may have two separate issues but I'd like to keep this all in one topic until it is verified one way or the other. I'm afraid until I get this figured out it will remain parked to avoid the possibility of causing some type of major damage or further damage. I have my thoughts of what to test and what might really be the problem but I will keep most of them to myself until I get some input here. I will have access to a DVOM and a vacuum pump on Monday to test the MAP and the BCS but that is then, and hopefully I can get some better ideas from all of you in the meantime.

THANKS

Check your coolant level. Open your oil fill cap and look inside. Describe what you see (condition of oil, sludge, etc). After warming the car up, check your oil. What color is the oil on the stick?

Depending on the accuracy of your fuel pressure gauge, your pressure is a bit low. The spec is 48 - 55 PSI. Also, try disconnecting the MAF sensor and see if things change. Did you include checking the vacuum T under the supercharger snout?

Willwren:The coolant is full, clear and bright green with no signs of oil or sludge (I flushed and changed with new the LIM gaskets about a year ago) The oil cap is clean with no signs of coolant in the crank case.(no milky residue) After warming the car the oil is clear and looks really good.

Archon: I indeed did check the t Under the SC. I also retested fuel pressure 38psi @prime, 44psi @idle, 52psi W/regulator unplugged. I unplugged the MAF with no change. The second time I started the car without the MAF it did trip the MIL and post a p0102 though. I did have a P0102 pop up a few times before right after I replaced the LIM gaskets but I cleaned the MAF and haven't seen it since.

Make sure no fuel is getting in the vacuum line to the fuel pessure regulator.
Make sure the boost bypass valve is moving 90 degrees without any binding.

I'd check the resistance of the primary & secondary windings of all three coils.
How many miles are on the spark plugs?

It sounds like you have a good sized vacuum leak but if that were true then you should be throwing a P0171 code.
Check the long & short term fuel trims with the car in park & the engine warmed up. Give us both readings at idle & then at 2,500 rpm.

Wait, you unplugged the MAF and it didn't change? Looks like your culprit right there. It should go from running well to running like crap if a properly working MAF is unplugged.

Good point. Add the MAF readings when you scan it at idle & 2,500.

Mechanical Mike: There is no sign of fuel in the regulator or line attached to it. The by-pass valve seems pretty smooth but when I actuated the arm the top third of the BCS feels somewhat rough. As for the coils, when the volt meter I am borrowing arrives I will test both sides of all three. The spark plugs have less than 10,000 on them, wires and plugs were all replaced when I did the LIM gaskets.

Now the fun begins, I started the car to my surprise it ran very smooth and acted normally. I left it alone for about 10min so it could warm to operating temp. Upon my return the MIL had turned on so I scanned the codes and there is two new codes present. P0102 (MAF low input) and p0108 (MAP high voltage). Prior to letting the engine warm up I scanned through the fuel trims and MAF readings, upon return the MAF had ceased functioning reading all 0's. Since it was warmed I did get the readings that Mechanical Mike wanted for the FT's, which are not so good at least on the LT trim, ok it's quite bad :sad5:

LTFT@ idle: 30.4 @2500rpms' 39.4 (i held the rpms' until the reading quit rising)
STFT@ idle: toggles from 0-3.4 @2500rpms' .7

I'd check the pins on the MAF, if all the connections look good then it's time for another MAF. I't one of if not the most expensive sensor on the engine, you might want to check the local junkyard.

Are you running a stock PCM? I've never seen fuel trims go over 20. I thought one maxed out at 16.4 & the other at 20. Let's resolve the MAF 1st then recheck the trims.