Start then die

Around the 20th of last month I detailed my engine, I've been told there are really no worries to doing this, I used some degreaser and the pressure washer from work. Anyhow, the next day 2 out of the 6 times I started it, it did nothing, no crank, no click nothin, afte about 4 times it started each time it did this, now I'm getting a good strong crank but no turn over at times, or it'll start right away then die, I wanna say its fuel related (maybe cloged injector?). But idk much about the ls1 or chevy really. Any positive help or advice is appreciated, I did check my spark plug wires on the driver side since they are the easiest for my big ass hands to get to, but can't really get to the pass in case it is spark related. Mods are as follows: SLP CAI kit minus the smooth bellows, cut out (open all the time), and skip shift elim. Its a 99 T/A M6, able to start without the clutch most of the time, and I've only had the car since January, again thanks in advance for any pos help, sorry so long, its my dd btw

Maybe get some contact / electric connector cleaner, and make sure it's safe on plastic, then undo the ecm connectors, clean them and re-seat them. Maybe clean the others as well, like the main injector & coil connectors. Might have caused moister & corrosion. Good Luck ! :cheers:

I'm not going to come down on your too hard because you're obviously learning a lesson here but for those that stumble onto this thread searching....don't use a high pressure washer on these engines. It really pisses them off. I don't recommend any water at all on them even though many people use low pressure and degreaser to clean theirs. Washing an engine with a hose dates back to the gen 1 and gen 2 motors. Those motors had a fraction of the electrical components these do. Combine that with the age of these motors now days and the age of the connectors it's just asking for problems.


I would recommend you start pulling connectors and letting them dry...water has obviously gotten to something. I would also pull the intake and check the knock sensors for water. Water has been known to get under the intake and kill knock sensors.

I looked back in my txts bc I had asked a friend if there were any precautions since he's a fellow ls1 owner and it was back on the 25th, living in tx I'd think it wouldve dried by now, anyways thanks for the help, really don't wanna pull the intake, also I plan on doing a full coolant flush ridding the system of dexcool, any recommendations on doing a full flush and a good dexcool replacement?

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Originally Posted by 0rion

I'm not going to come down on your too hard because you're obviously learning a lesson here but for those that stumble onto this thread searching....don't use a high pressure washer on these engines. It really pisses them off. I don't recommend any water at all on them even though many people use low pressure and degreaser to clean theirs. Washing an engine with a hose dates back to the gen 1 and gen 2 motors. Those motors had a fraction of the electrical components these do. Combine that with the age of these motors now days and the age of the connectors it's just asking for problems.


I would recommend you start pulling connectors and letting them dry...water has obviously gotten to something. I would also pull the intake and check the knock sensors for water. Water has been known to get under the intake and kill knock sensors.

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:werd:

I went to start my car after work a little bit ago and when I turned the key all it did was crank, did it twice, then I turned the ign on/eng off a couple times then it started, could the vats possibly be acting up, I work for Toyota and I know on the cars with immobilizer keys (essentially what we have) if it doesn't read properly it'll crank and crank etc, obviously I'm trying to avoid having to tear it apart as I don't really have time or any really know how, especially working for/on toyotas

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Originally Posted by Red99TA

I went to start my car after work a little bit ago and when I turned the key all it did was crank, did it twice, then I turned the ign on/eng off a couple times then it started, could the vats possibly be acting up, I work for Toyota and I know on the cars with immobilizer keys (essentially what we have) if it doesn't read properly it'll crank and crank etc, obviously I'm trying to avoid having to tear it apart as I don't really have time or any really know how, especially working for/on toyotas

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if it were vats your security light would be on and vats disables the fuel AND the starter. If I didn't know you put water to it I would recommend checking your fuel pressure. The next time it does it cycle your key again and see if it starts up. A pump that's having trouble building/holding pressure will do that.

cool thanks, would it help to know that i don't fill up till the light comes on? Wasn't aware that keeping a 1/4 of a tank of gas is ideal for the pump (obvious noob if you will), I also figure the car hasn't seen regular driving like this, bought it in mid to late Jan of this year with 79,900 on it and now it has 86,240, which is also why I was inquiring about the coolant switch, I noticed when it was cranking the fuel gauge dropped al the way each time it did the crank issue, didn't really look at it when it started, so again what is an ideal replacement for a coolant swap, also gonna need brakes soon, been thinking about the cheapest hawk pads but open to reasonably priced suggestions as the wife and I are expecting, and thanks Orion, you seem to know your shit

that gas keeps your pump cool so you really don't want to make a habit of running it all the way down. The best thing is to just start diagnosing it.....try cycling the key next time and if that makes it start right up then it may be time to throw a pressure gauge on the end of the rail and see if it's making and holding pressure ( should be ~58psi).
As far as the coolant I'm not sure what to tell you. I just used prestone all makes antifreeze when I refilled mine after the heads/cam a couple years ago. You don't want to mix dexcool with regular antifreeze though so pick a horse and ride it. :D

Here's a pretty good read on the differences between red and green antifreeze. Not sure if it'll help you but it might have some useful info in it.
red vs green

reference chart

I think I'm gonna do an "all make" coolant as well, suppose I'll need to go with a new t-stat as well. I did a search on how to do a complete flush, drain rad, then have a hose running while the eng running, prolly should have the heat full blast as well so the heater core gets flushed as well (not sure if thats true or not?). My only fear is having to guess how much water is in the system after its ran clear out of the rad since 50/50 is of course the ideal number(s) for coolant, also will doing it this way drain the overflow or does that need to be sucked out and washed etc? Again, thanks orion don't mean to bother, just really cautious of how it needs to be done right, everybody has a dream car in mind, I'm just lucky enough to own mine, too bad its my dd tho

Had a chance to do a little diagnosing and I have to say its the pump, this morning when i went to start it, I turned the key 3 times to the ign on position then back off, then I went to fully start it and it started the first try, after work is a diff story, not so much luck, I turned the key quite a few times and nothin, then all of a sudden I actually heard the pump kick on, my only question now is, how long can I keep doing this nefore its completely dead? One more ques. lol, will this effect my mpg? Good diagnosing tips Orion, your help is greatly appreciated

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Originally Posted by Red99TA

Had a chance to do a little diagnosing and I have to say its the pump, this morning when i went to start it, I turned the key 3 times to the ign on position then back off, then I went to fully start it and it started the first try, after work is a diff story, not so much luck, I turned the key quite a few times and nothin, then all of a sudden I actually heard the pump kick on, my only question now is, how long can I keep doing this nefore its completely dead? One more ques. lol, will this effect my mpg? Good diagnosing tips Orion, your help is greatly appreciated

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have you not been hearing the pump prime when it doesn't start? Start paying attention to that. When you turn the key you should hear the pump prime. I would look at those relays...the box with those relays is in the engine bay by the drivers side wheel well. Might have some water in there. Pull the fuel pump relay ( box lid is labeled) and look for moisture and maybe try to blow out the terminals for the relay with compressed air. You could also swap it with the a.i.r. system relay.
If you're not hearing that pump prime then it's time to start diagnosing the pump and see if it has 12 volts back there or not. If the relay and/or box isn't wet then I would next verify 12 volts at the harness going into the tank. You can unplug the plug just before the tank (the plug is on the rear firewall drivers side just above the rearend) and check the grey (+) and black (-) wires for 12 volts (make sure you check the car side of that plug and not the tank side). Good luck. I have a feeling that fuse/relay box up there probably got drenched in water so do what you can to dry that out. Pull the relays and leave the lid off that box in the sun for a day would probably help if you don't have access to an air compressor.

I'll check the relay tomorrow, this morning it started first try twice, then after work it took a little while, but not like yesterday, but when it started ater work today it backfired (twice i think, 2 quick pops), could this be due to the pump possibly not putting enough psi out to start the engine but putting enough gas to have an extra amount so that when it does start theres extra fuel being ignited? I've been told it bc of what it did as far as backfiring it could be ignition related, so fuckin frustrated right now, but I'll never be pressure washing my eng and won't let the tank get below 1/4 any more either

I was off today so I tinkered with the relays a little, took of the fuse/relay cover, seemed pretty dirty so i blew some of the dirt/dust out (dont have a compressor at home so did the best I could with my mouth lol), with the AIR relay in place of the fuel relay, I turned the key on and the pump came on right away all 3 times, removed the AIR relay, put it back in its place, blew on the terminals of the fuel relay and again blew in the box itself, put the fuel relay back in, made sure it was all the way in incase it wasn't before, turned the key three more times and pump came right on all three times, and even started right away once tried to start, came back out a couple hours later and pump still came on right away, started right away, so I wonder if maybe dirt/dust was making it have a possibly bad connection? or possibly not all the way in the slot making a bad connection as well, either way its 3 for 3 for starting right up, and no backfiring either, hopefully this was the cause