ClubRoadster.net banner

1 - 20 of 34 Posts

·
Registered
Joined
·
104 Posts
Discussion Starter · #1 ·
Ok long story short I overheated my car and cooked the head. Since it was warped and needed to be heated to be straightened I opted to buy a new head. Found a head on ebay bought it, had it tested and a 3 angle valve job done professionally. The car sat for about 3 months during this whole process by the way. Put the new head on and the car wont start. Actually it will start and run for about 2-3 seconds before dying. The timing is not set yet because I cant keep it running. So to narrow it down I had my mechanic check and recheck the timing on the cam gears to make sure we're not a tooth off. Everything looks good there. So next step I used a tester to make sure all four inijectors are getting a pulse, which they are. Checked the plugs and wires by removing one at a time and testing for spark. Good there too. Checked fuel pressure at the line and got 45psi there too. I just can't figure out what else is going on here. I'm working on the assumption the car hasn't thrown any codes since it only runs 2 secs at a time. The car doesn't seem to respond to throttle input as it just dies same weather i put my foot on the gas or not. What should I look at next? Pull the injectors to see if they are actually flowing gas? Any help would be greatly appreciated since I've been without my baby for about 4 months now, and I miss her. But the good news is that in the down time and while she was on jackstands anyway I installed the Tein hyper flex coilovers and edfc.
 

·
Registered
Joined
·
332 Posts
MAF. it could be that. when a MAF is bad, it usually lets the car run for about a few seconds before it shuts it off. if you just let the MAF out and get it wet..it could be that
 

·
Registered
Joined
·
153 Posts
Yup check and see if the maf is plugged in. I forgot to plug mine in and it kept dying on me the other day then i realized it was unplugged.
 

·
Registered
Joined
·
153 Posts
I already gone through 3 maf's on my car. Just take it off and if the flap is flopping around then it's a goner. If it's still good it sound stay closed and you can push the flap in and it will spring back to close
 

·
Registered
Joined
·
104 Posts
maybe your gas went sour.cas sensor might be done.also try adjusting/rotating the cas sensor to semi set the timing.but also sounds like a maf problem.
 

·
bad mother f......
Joined
·
3,173 Posts
A couple things to check...

as others said check that MAF out. If it is unplugged the car will act exactly as youre describing.

On the passenger side of the car on the intake tube near the TB make sure that little hose from the intake tube to the IAC is connected. If it isnt, your getting air past the MAF the computer cant make the injectors count for. this will also make the car do as youre describing.

One more thing- since you had the head off, make sure you did not swap the fuel lines, the car will not run with the fuel line backwards. I believe the hose with the white dot is return. you have fuel and spark so I dont think its your crank sensor.
 

·
Registered
Joined
·
1,999 Posts
MAF test is easy.

I believe it's hit pins 3/4 with a multimeter set to measure resistance (They're the only 2 pins that'll give you reading). I believe the measurement you're looking for is between 2.25 and 2.75v at 60+ degrees.

Additional test. Breathe warm air over the hotwire, and you should see the resistance drop.

[Edit: whoa, that decimal was way outta place! ...and I agree with these guys. MAF.]
 

·
Registered
Joined
·
104 Posts
Discussion Starter · #16 ·
Thanks for the help. I was wondering if the maf sensor could really have such a profound effect on the car running. I figured it would at least run, even if poorly. I've discussed it with a few friends and they are all stuck on it being the timing. They believe it has to be a tooth off on the timing belt. But I have a well versed mechanic (Jimmy at Fuji Racing) that installed the head and double and triple checked the timing. Like I said I have not set the timing at the CAS. I was wondering if it could be off enough to cause this. I was planning on trying to start with the timing in a few different spots. Jimmy and I haven't been able to dial it in yet since it won't stay running. I dont have a multimeter so i cant check my maf. I might be able to borrow one tomorrow.
 

·
bad mother f......
Joined
·
3,173 Posts
Even if it was a tooth off, it would still run. I still think you have a MAF related problem.
 

·
Registered
Joined
·
104 Posts
Discussion Starter · #20 ·
Alright tried a buddies MAF today and still same thing. The car starts and will barely idle if the gas is depressed all the way. If I move the CAS around the car changes tune obviously. The exhaust is coming out in puffs and smells of gasoline. When I turn the CAS all the way counter clockwise (from front of car) it seems to run better but still wont' idle or stay running. I will post a pic of my timing in a few to see what you guys think. Ant other ideas?
 
1 - 20 of 34 Posts
Top