C36 NS after sitting for a few months then head gasket replacement. Checked/replaced about everythin

[tcles]

I have a '95 C36, the head gasket blew back in may and it was sitting all through the hot months in my carport because it was too hot during the end of spring and all of summer (temp never drops below mid 90s even in the middle of the night in Phoenix) Finally about a month and a half to two months ago I ordered the head gasket, and timing cover gasket and went to work. Got the head out, resurfaced and cleaned for just over $200 (even set the cams to TDC) scotch pad/ATF/MEK/Brillo cleaned off all gunk and rust in all the cyls till all were as smooth as a baby's bottom. placed the new head gasket and head on put everything back together correctly to my knowledge, another C36 owner who has extensive experience doing automotive work assisted most of the time. It cranks, no start. I checked the wiring, especially the part of the harness I cut out and reinforced before sauntering back in (the part where the ignition wires split from the harness before going under the cover, anyone with a highermilegae c36 knows what I mean) This part was working fine before, but I made sure to resolder the common ground going into the rest of the harness as the amount of solder holding the three grounds to the harness makes this a weaker junction. I replaced all the spark plugs, I replaced the air temp sensor and the camshaft position sensor, crank sensor tests on the ohm meter over 1k, all the ignition coils and the fuel injectors tested the same as each other on the ohm meter, so all those components seem to be fine, I replaced the fuel injector seals and timing belt. replaced both the metal seals for the chain tensioner because the old, damaged ones were causing a severe oil leak as this is a pressurized area for oil. Just got the camshaft sensor in the mail and got it to start for the second time ever since the head gasket and it quit after about 3 mins, and ran kinda hard, probably due to carb cleaner that I had been using to test to make sure the plugs were firing. The only other time it started was immediately after I replaced the air temp sensor and it ran for about 10-15 seconds and I cut it off due to rattling and the fact that I didn't expect a start so I wasn't sure everything was tightened down all the way. Both times it started the car had not been messed with in any way whatsoever for at least 24 hours (while I waited to obtain parts)
I'm pretty sure the fuel system is fine as it squirts a pretty healthy stream when you press the test valve on the rail, and the cyls reek of gas when you pull the plugs out as well as the exhaust after attempting cranks, and really the whole damn car seems to just reek of gas in general after messing with it for a bit. placed 3 gallons of premium fuel in there and the gas level showed maybe a gallon left or less before that, the fuel gauge now shows a quarter tank since I placed the gas in the car so I'm somewhat sure all the old gas has been pumped through and it's only trying to ignite new gas. My current attention is more on the ignition system still since I know it works since it does ignite carb cleaner, but it doesn't seem to be very consistent. Before I start tearing up the harness and finding someone to crank the car while I check to see if the plugs are firing (Randy hasn't been as available lately and it's hard to find anyone else to help out at all, not even untrained people to crank it while I check things bunch of haters I swear!)
I have also replaced the battery with a brand new one from napa, I have a battery charger, I'm about to put the battery on that again, but I don't think the battery being low is the problem.
The two times it has started have given me two leads that may or may not pan out that I want to exhaust before I start tearing up the ignition system:
1. Reeking gas smells indicate to me that the fuel system is fine, but could too much gas be the problem and the engine has been flooding. Both times it started the engine had not been messed with at all for at least 24 hours and it started quite easily on the first attempt to crank it, but never again afterwards. The first shut off being due to me cutting it off, and the second shut off was caused by the common ground coming undone, but I tried to crank it again without hearing firing again for a bit before I reached that conclusion and tore open the harness and repaired the junction again. Now it seems to be firing a little irregularly again but having more trouble then before, yet I'm almost certain this ground is secured better then it was when it started.
Could the engine be flooded with gas and that be the problem, if so what do you all suggest?
2. Both times it has started I had just replaced a sensor that had previously been completely busted showing absolutely no reading on an ohm meter, could the engine management system or ecu be acting up? once again your thoughts and comments on that.
I'm going to plug the battery into the charger and let it mellow for a bit unless randy can stop by in case the engine flooding is an issue. I'd really like to know if any of you think this is a possibility at all or is this idea ludicrous. I know randy pulled out the voltage relay in the engine management system's little compartment in the back passenger side and didn't say anything about it being bad so I think that is probably fine but do any of you think things point to there and if so what would I do to test it more thoroughly.

Your comments and ideas would be greatly appreciated, I have worked very hard on this head gasket replacement, especially since I've had to do most of it completely by myself, even broke an engine lift which now serves as a light stand for my work light. I've read up quite a bit from many sources including the WIS disc (not as much help as I was hoping for the c36 since it's NOT THERE so I kinda have to split between c280 and E320 info depending on whether the problem is part of the w202 or m104) and as far as I can tell I've really patched up everything I could think of or find info on. Once again the crank sensor is very easy to test on early c36's since it has a wire that runs all the way up topside and connects with one of the 1 pin connectors like the ignition coils, air temp sensor, and cam sensor that runs all the way into the management system's compartment, so it doesn't even need to come out to be tested, and tests very steadily over 1k, I know a lot of folks will immediately think that's the problem due to the nature of what has been happening, I'm about 95% sure it is not, I am pretty darn sure the engine shut off due to the common ground getting jiggled until the solder snapped, but now that I have melted most of the old solder off and reinforced it well (and I can hear some firing again) it isn't even getting close to starting.

Thanks in advance, here's the odometer, my goal is 500k! Go M104!

[strictlyspeakin]

Did you rotate the engine by hand at any point?

[Spikes]

Hi
Sounds as if the ignition sensor is way out. Did you rotate the engine while you had the head off? Recheck alinement's of the camshaft position sensor in relation to TDC
Good luck
Spikes

[tcles]

Yes ive rotated it by hand many times. I always rotate it by hand fully at least one rotation if i at any point take out the chain tensioner just to me make sure that i dont bend any valves or have the chain caught up and damage the chain or front cover.

[Sulaco]

I think I've read somewhere that the tdc marks on back of the cam gears isn't tdc on the 3.6 amg m104. I did this job on my 2.8 m104 and it fired right up. You definitely know what you're doing, so I would imagine there's something weird going on with it. Have you got it started yet?

[strictlyspeakin]

I asked because I was wondering if you were TDC on the wrong stroke, exhaust stroke and not the compression stroke. Sorry, but I've got to ask, have you confirmed this?

[tcles]

I asked because I was wondering if you were TDC on the wrong stroke, exhaust stroke and not the compression stroke. Sorry, but I've got to ask, have you confirmed this?

The Crankshaft shows TDC both at dead center and 180 off because the crankshaft just spins twice and repeats its sequence for every full rotation of the camshafts. When I took the head off I actually had it set 180 off and marked it that way, and was puzzled about where the heck my marks went when I was putting it back together until I realized the crank goes around twice.

But The timing is fine as far as I can tell, well right now it might be a little off from adjusting it to see if it was effecting the current problem, and I'll probably try and set it back because it started up and ran with the timing sounding fine. The car sounded exactly the way it did before the head gasket repair except that one piston wasn't firing and gasoline could be smelled making us think there was a misfire. That's the only time the car started up and ran in a manner that seemed like it would last indefinetly.

I had noticed for awhile now a peculiar occurence that any time the car started it up and ran for any length of time it was always the first attempt to start it and the longer the car had been sitting without being messed with, the easier it would start and the longer it would go until puttering out.

I have now figured out that this issue is due to engine flooding, when I take the fuel pump relay out and turn the key the car will actually start up and run until it consumes all the gas that was already pressurized in the rail. With the relay in the cyls get soaked way faster then the engine can catch and turn over and a spark plug or two will usaully get so wet that I have to either let the car sit overnight or take out the plugs and dry them in open air (if I do this I'll spin the motor to eject all the gas, but letting the car sit still is the only way to get it really really really dry). Due to some plugs seeming to get too wet to spark and some being able to fire fine once the excess gas is cleared out of the engine, I'm thinking the issue is either completely or mostly effecting specific cyls. I thought the issue was likely to be vacuum leaks even though there really weren't any new significant sources of leakage I could tell and the car still ran with any that existed, I still used the hot glue gun, rubber hosing, and jb weld, and I'm fairly sure that there are no vacuum leaks now. I sprayed the various parts of the intake down with carb cleaner and tried to start the car without the fuel rail in after all the fuel had been ejected and there didn't seem to be any getting sucked into the intake.

I noticed though that the large harness connector that wraps around the big bosch air pump on the divers side in the HFM section of the compartment was a bit loose so i got it in really good and when I tried to start the car I realized that I hadn't been hearing that noisy whine coming from the air pump so I figure that might be working in my favor. I gotta get a good start out of the car where it runs for a few seconds to get that air pump and the front fans to start kicking on, I'm kinda at a loss as to why it's pumping so much gas into the engine unless one or more of the injectors is getting stuck open. If it is it isn't because of improper signaling, I tested all the injector wires with a noid light and they are all blinking about the right rate, I figure if I determine the injectors merit a closer look I'll have to rig up a test bench kinda rig to deliver current to the injectors so they open allowing me to pour solvent through them and inspect them to make sure they are mechanically opening and closing all the way. It might be time to rebuild the injectors anyway, but that just seems really freaking bizarre that the injectors would all of a sudden not be working when they were operational before. The car has been sittting around for quite awhile maybe some crud dried up in there and is preventing the valves from closing all the way on the injectors, if that were the case it wouldn't be spraying fuel that's been properly aspirated.

I was actually going to take a really close look at the injectors before but it is such a damn PITA to get that fuel rail off, whoever's bright idea it was to put those allen head bolts in the exact spots where the supports for the fuel rail block off just about every mechanical means of access with an allen head wrench or nut driver, AND make sure that the amount of clearence is so small there is no way to get a swivel in there either, yes that engineer is some kind of sadist I'm sure. I honestly think tightening/loosening the two most poorly placed of these bolts (the one in the middle where the little strut for the fuel rail, the throttle body housing, breather hoses, everything is in the way of accessing it, and the one in the veeeery back, on the bottom where they had the bright idea of having that lump of steel come up and block the only clear means of access, It took me as long to get that one out as the rest combined, I had to do eighth turns with a short handled allen wrench, which was of course frequently dropped into the back of the compartment but was actually nice to get a break from getting that LOONG bolt out an eighth turn at a time while fully stooped over the compartment as this is the most inaccessable part of the whole compartment unless you are cryss angel and are able to levitate. REALLY kills your back)

I'll see what's up, if anything I mentioned seems like something any of you have encountered, let me know so I can jump to that since I'm still yet to fully narrow down the exact issue itself. I'll probably also run the ohmeter around to all the electrical components, but I tested everything before and it was all square within specs, but it's not that much work and would prevent a crapload of work if something did mysteriously go bad while the car has been sitting doing nothing in the past couple months.

Edit: In my opinion the fuel rail is actually the biggest pain in the ass out of all the dissassembly reassembly under the hood on the c36, yes way worse then the chain tensioner. I've actually gotten pretty good at putting in the chain tensioner by myself after all those timing adjustments, the trick is take a good at least half hour or hour break before trying to do it, if you've been dismantling a car, you wont have the strength to force that sucker in flush and turn at the same time, the vector all your force needs to be going in is the absolute most inconvienent, angled up towards the block from under the air filter box, this is absolutely no fun to do from hunching over the top of the car, but still way move fun then removing a like inch and a half long bolt that's threaded top to bottom, at an eigth turn at a time, hunched over the engine the entire time....

[strictlyspeakin]

I feel for ya. My back is sore just thinking about it. I've installed a front strut brace which serves me so when I need something to hold or lean on/over.

Since you think it is flooding, have you identified which cylinders seem to be affected?