Starting problem

[Halon]

As of like 3 days ago, my car all a sudden started having a starting problem. When I go to start it, it'll start but not fully. It'll just kinda start for about a 1/2 second, never go above 500rpm, and die. Kinda sounds like it fires barely and just kills. So far I have checked compression which is 150-150-145-150. There is a spark present on all 4 plugs. I took off the return line from the FPR and turned it over to make sure there is gas pumping through, and there is fuel. Base timing is set at 8BTDC when the plug is grounded.

This is a 91 talon awd. Mods are 50-trim, exhaust, intake, 2g MAS, EPROM ECU with keydiver chip. 650's, 255hp... The only thing I can think of is maybe it has something to do with the fact that I'm running the 255hp on a stock FPR. But then if that's the case, why was it starting for the past week and a half just fine?

Anyone have any insight?

[GVR-4579]

leaking injector flooding out the car when its not running? Vaccum leak?

[Halon]

what's a good way to check the injectors for this? They are brand new, only been used for 1 1/2 weeks. I'm pretty sure I don't have any vacuum leaks as I have minimal vacuum lines and I did a quick look over and didn't see anything. But I will test that also. Not to second guess you, but how would a vacuum leak cause it to not start sometimes, and then start other times? And wouldn't it cause other issues while the car is running like idling rough?

I guess I did forget to mention a few other things. The car does start sometimes. Like 1 out of 20 attempts and it might start. And when it does start, it runs just fine, idles just fine. Also I have looked for leaking gas, and nothing is wet anywhere near any fuel lines/injectors/fuel rail. After I attempt to start it a few times and it won't start, you can smell gas.

[GVR-4579]

maybe check your tps too, i know my datalogger will check injectors, i doubt if they are brand new that they are bad. If you were getting unmetered air in the maf would be wong, i had a problem withthis once from my BOV but then again i am not recirculating Does there seem to be any specific time that it does it worse or more predictably or just al the time do you now what your fuel pressure is?

[Halon]

I'm not sure what my fuel pressure is. I don't have a guage for that so I'm sort of unsure how to check that. There is no specific time it does this. It just started doing it a few days ago, and it's just gotten worse every time i drive it. What seems to have been working is I pull the MPI fuse, and crank the engine over for like 5 seconds trying to get everything out of there that I can. Then put the fuse back in. This works sometimes after just 1 try, or after 10 tries other times. So I'm not sure if it's actually helping, or if it's just coincidence. If I can get the car to start, I too have the ability to shut off the injectors 1 by 1 with my logger. Maybe that'd be a nice quick way to see if they shut off. Also how can I check my TPS? On the logger it would show the throttle at around lik e8% at idle, and 100% at WOT. That seems about right to me, so can I assume it's working fine?

One last thing I noticed a little bit ago. The little solonoid that the FPR vauum lines connect to, it was ticking real fast, kinda sounded like a little relay was just going apeshit in there. We unplugged it and plugged it in again. It started, but then I shut it off and tried again and it wouldn't start again. So there I'm also not sure if that actually did something, or was just a coincidence. What I did after that was take one of those other solonoids right next to them that I'm not using anymore (emissions are removed), and hooked up the vacuum lines and connector to it, and it didn't fix a thing. So I'm thinking that is probably good as well.

[quick2.4]

Its an idea but it might not be fuel related mine is more stock an was doing th same thing but it was a rotted wire at the alternator which was giving a bad connection to the battery so you might wana check you charging system out just to be sure

[Halon]

How would charging have to do with this? The battery is working fine, the car is turning over fine. The problem is that it turns over, over and over and over, and nothing happens except for it hicups for a second like it wants to start but just dies.

[1QUICK4]

leaking injector flooding out the car when its not running?

I was thinking the same thing, it's a pretty common problem.

Get it up to operating temp then shut it off & let it sit for awhile.
After it sits for about 10 minutes pull your sparkplugs and see if there is more of a heavy gas smell from one of the cylinders. You could also pull your fuel rail out (with the injectors still attached) and see if one injector (or more) are leaking.

[Halon]

Thanks. I will look at that here when I have some spare time! I bought these injectors while I was in Japan probably like 8 months ago from SLS. But I just got the car working 2 weeks ago so they have like 200 miles on them only. So I'm thinknig I'd probably be screwed if they are bad because I ordered them so long ago eh?

[Outlaw1]

Are you sure the MAS is good and/or plugged in? Are the spark plugs fuel fouled?