horsepower_junkie

iTrader: (4)

Hey I just got the motor/trans stuffed back in my 01 b4c after being completely rebuilt. Motor was junk when I bought the car so I started from scratch. Its pretty well stock other than slp longtubes and a custom grind comp 252/256 .595/.595 cam. I got it all thrown back together and it fired right up... But only for ten or fifteen seconds and died and won't start back. I have good compression (about 235-240 psi), its timed right, replaced cam and crank sensors, all fuses/relays under the hood are good and I have 60 psi fuel pressure. If I unhook the battery and walk away from it for thirty minutes or so when I hook it back up it will fire for a second like its starting then die again and do nothing but spit and sputter while cranking. I thought it might be maf so I unhooked it and tried to make it default to speed density but still only would sputter. O2s are hooked up. Any ideas?

Lopoetve

iTrader: (1)

Maybe the cam is to aggressive for it to idle? Will it stay running if you give it a bit of throttle?

horsepower_junkie

iTrader: (4)

It wouldn't with the maf plugged in but I haven't tried it yet leaving it unplugged. I have not had the car tuned yet but I figured it should at least show some signs of life a little better than spitting and sputtering. I might be wrong though! Is there any way to test the maf with a multimeter or anything?

Lopoetve

iTrader: (1)

I'm sure there is, but I don't know what it is.

TooLateVTEC

iTrader: (2)

Try giving it some gas when it fires up and hold it around 2000. With that monster camshaft in it, it is NOT going to want to run with the stock tune...its gonna need some help.

Just remember to watch the oil pressure when it starts up.

Full-Force

iTrader: (11)

I have seen this happen on big cam untuned engines. It gas fouls the plugs. Try this. Hold the gas wide open and see if it will crank. If not, take the plugs out and either replace them or burn them clean with a torch. A lighter will work if you hold it on it long enough.

When you get it running you need to either get osme idle tuning or adjust the bumpstop on the TB so it will get more airflow. When you do this you may need to reclock the tp sensor by elongating the holes in it and filing off the tang so it can be adjusted.

caseypryan

iTrader: (10)

Maybe it needs gas.. jk haha

edwardzracing

iTrader: (59)

Assuming you didn't change injectors, right? Would DEFINITELY need a retune if you increased the size. You used some heads that will work with that camshaft, right? If you used stock heads, your valves are kissing the pistons BIG TIME. I have to assume you changed the heads or the motor probably wouldn't even start, but I honestly don't have enough experience with pistons hitting the valves to know if the motor will run or not. After reading the size of duration on that cam, I'm honestly hoping you didn't put stock heads back on or any head close to 62CC's. Otherwise, I'm going to have to lean towards some bent valves. If you are sure that isn't the problem, then my guess would have to be tuning. Adjust the throttle blade screw a tiny bit, and reset the TPS by unplugging it, turning the key to the on position for roughly 30 seconds, then turn the key back off, plug the TPS back in, and turn the key to the on position for another 30 seconds, and then back off. Now try to start it and see if the little bit of added air helps at all. Make sure the spark plugs are dry, and let us all know what happens. Best of luck. Keep us posted... always like it when a "Problem" thread gets started it and the original poster posts back with what the problem was.

horsepower_junkie

iTrader: (4)

Got it figured out. It just took a bit to get it to go ahead and fire. I left the mass air flow unplugged to default to speed density and gave it quite a bit of pedal and it fired up although it won't even think about idling until I get a good tune on it. I am planning on changing injectors, maf.... just a broke college kid at the moment and am doing what I can to it when I got a little extra money. As for bent valves-I used a pretty thick gasket and there is NO piston to valve clearance issues at all. I did use stock heads although they have been SEVERELY modified (port, polish, just resurfaced no milling...) All the big ugly stuff internally is done... Just got the expensive bolt on stuff left to do! But its up and kickin now. Thanks for the help guys! The mass air flow is bad obviously so i am on the market for one... Any suggestions???

Lopoetve

iTrader: (1)

I wouldn't say the MAF is bad, it may just be that far off that stock tune using it can't function.

Get it tuned first, then test that thing. Might not have to spend the cash!

edwardzracing

iTrader: (59)

+1. Glad you got it figured out. I'm still stunned you fit a cam with more than 250 duration and stock heads. Wow. Kick ***. Enjoy it.