[nitehawkjcb]

I got everything back together, but the car's running like sh*t. I'm not throwing any codes that I wasn't throwing before the build, all the wires are in the correct firing order, injectors are pulsing an average of 2.8, which was what they were doing before. Vacuum is at 20 inches, until the car starts to stumble and misfire, which is absolutely random. I'm going to get new spark plugs and wires (plugs have less than 2,000 miles on them, wires have ~10,000 on them) and hope that helps. Any ideas are welcome and appreciated.

[zipper778]

Does it seem to be burning any coolant or oil? That is kinda weird if everything is the same before the build. Also, what all did you change?

[nitehawkjcb]

I've only had it running a total of 20 minutes. I changed the head gaskets, LIM gaskets, supercharger gasket, rocker bolts, head bolts, throttle body gasket. The only "mod" that was done was the heads being ported and the valve job. Something else odd - I had loose vacuum connections, and the car would actually stay running decently, but I fixed those connections and now it won't stay running longer than one minute.

Oh, and no burnt oil or coolant.

This post has been edited by nitehawkjcb: 26 February 2010 - 04:58 PM

[blazerman3]

nitehawkjcb, on 26 February 2010 - 04:51 PM, said:

I've only had it running a total of 20 minutes. I changed the head gaskets, LIM gaskets, supercharger gasket, rocker bolts, head bolts, throttle body gasket. The only "mod" that was done was the heads being ported and the valve job. Something else odd - I had loose vacuum connections, and the car would actually stay running decently, but I fixed those connections and now it won't stay running longer than one minute.

Oh, and no burnt oil or coolant.

Should`nt you be pulling more than 20 inches vaccumn? Ignition packs are fairly new?

This post has been edited by blazerman3: 26 February 2010 - 05:25 PM

[nitehawkjcb]

blazerman3, on 26 February 2010 - 05:19 PM, said:

nitehawkjcb, on 26 February 2010 - 04:51 PM, said:

I've only had it running a total of 20 minutes. I changed the head gaskets, LIM gaskets, supercharger gasket, rocker bolts, head bolts, throttle body gasket. The only "mod" that was done was the heads being ported and the valve job. Something else odd - I had loose vacuum connections, and the car would actually stay running decently, but I fixed those connections and now it won't stay running longer than one minute.

Oh, and no burnt oil or coolant.

Should`nt you be pulling more than 20 inches vaccumn? Ignition packs are fairly new?

I'd have to say no - usually on these motors with a stock cam, usually 19-23 inches is "normal". The ignition packs probably have 90,000 miles on them total, unless they were replaced before I bought the motor.

[blazerman3]

Change the packs too, and see if that helps. Worked great for our 2 cars.

[me6894]

Don't just go and buy new coil packs that's a waste of time and money. Do you have a scanner to scan for misfires? Unplug the maf with it running and see if it runs better.

[3800power]

20" is okay for vacuum. I would shoot for more like 21-22". That probably is not your problem though, go with what Matt said and check for a faulty sensor.

FYI while the car is running, spray some things down with some carb cleaner to see if there is a vac leak. For example, injectors at the o-ring, vac lines, etc.

[me6894]

Also did you crack the vacuum t that goes into the LIM? If its the original its probably brittle and cracked.

[nitehawkjcb]

It doesn't run at all with the MAF unplugged. When it was running without cutting off, I unplugged the MAF and it chugged and tried to die worse. None of the vacuum T's or anything are original. I replaced all of them. The only scanner I have is an Aeroforce.

It was throwing a P0300 and a MAF code, but I cleared them and they didn't come back. (Before I even took the motor apart I was unplugging the MAF because the old MAF was bad, and unplugging it did make the car run without stumbling.)

This post has been edited by nitehawkjcb: 26 February 2010 - 07:51 PM

[3800power]

What all did you even change on the car man, it would help if you put down your mod list. All I remember is the ported heads.

[nitehawkjcb]

Ported heads, plog, ported rear exhaust manifold, 3" downpipe, autolite 104's, underdrive alt pulley, 180 tstat, p & p blower, LIM with coolant ports blocked, walbro pump.

[nitehawkjcb]

Update - it threw the MAF code again (P0102). I'll check the wires going to the MAF to begin with. I'm kinda pissed though, I bought this MAF from Morad and he claimed it worked. Well, I'll see if the wires are good going to it, and if not then Morad will be getting a call from me.

[bumpin96monte]

Even if it is a bad maf, the thing should still run fine with it unplugged- something must be wrong there.

This post has been edited by bumpin96monte: 28 February 2010 - 02:42 AM

[me6894]

bumpin96monte, on 28 February 2010 - 02:12 AM, said:

Even if it is a bad maf, the thing should still run fine with it unplugged- something must be wrong there.

Unless for some reason his ve tune is way off

[3800power]

me6894, on 28 February 2010 - 12:24 PM, said:

Unless for some reason his ve tune is way off

Even if he was running a stock L67 tune his car should still idle fine. Even with how slopped together my tune was when I first put the cam in my car, it still idled fine, and drove fine, it just didn't have the VTEC (XP FTW!) yet.

[bumpin96monte]

Thats what I was thinking- when I first put my whipple on (already had all the other mods done w/ the swap)- I reflashed a new tune since I put in new injectors with the whipple- and I put the stock VE table in (and base MAF table for the 85mm)- and it still started w/o the MAF. It was definitely running more roughly than normal, but it still started and idled.

[nitehawkjcb]

A little update. It's acting weird. Yesterday, the car started and idled fine for about 5 minutes, then I shut it off and went to work. I just started the car a few minutes ago and it idled for a couple seconds, then stumbled and died. I restarted it with the same result. I'm going to buy a fuel pressure gauge tomorrow probably. A question though - if the IAC went bad, could I unplug it and see if the car idled then?

[me6894]

nitehawkjcb, on 01 March 2010 - 03:30 PM, said:

A little update. It's acting weird. Yesterday, the car started and idled fine for about 5 minutes, then I shut it off and went to work. I just started the car a few minutes ago and it idled for a couple seconds, then stumbled and died. I restarted it with the same result. I'm going to buy a fuel pressure gauge tomorrow probably. A question though - if the IAC went bad, could I unplug it and see if the car idled then?

No because the iac motor would just stop where it was at and it would idle the same. They do make an iac tester though.

[nitehawkjcb]

If the ground wire had an intermittent connection, would it cause the car's random symptoms? The ground wire is on a stud, tightened with a nut against the coil bracket. The coil bracket is also black (so I'm assuming it's painted), perhaps this is causing the problem?

[3800power]

I was having problems with my car originally, so the way we figured out it was not that ground was we ran a wire straight to the ground on the battery. Granted you can't do that DD, but while it was in the garage, we did that to rule out that being the problem.

[RICH17]

are you using a different MAF? Cause if youre running like a LQ1 MAF and have a leak past the MAF in the intake system than the computer will be reading less air than what you're taking in. Know from expeirience

[nitehawkjcb]

Nope, running a stock MAF.

[blazerman3]

nitehawkjcb, on 02 March 2010 - 09:39 PM, said:

If the ground wire had an intermittent connection, would it cause the car's random symptoms? The ground wire is on a stud, tightened with a nut against the coil bracket. The coil bracket is also black (so I'm assuming it's painted), perhaps this is causing the problem?

Could be part of the problem...clean it to bare metal and secure it...then paint over the stud to keep the corrrosion out

[nitehawkjcb]

It's not the ground wire. Every time I start the car now, it shuts off after two seconds. I just ordered a fuel pressure tester, and I will be changing the fuel filter the next chance I get, and the pressure tester should be here next Wednesday/Thursday, so I'll change the filter and check the pressure.

I have heard of an Idle Air Motor in Jeeps, perhaps my IAC is messing up as well, but I thought it would throw a code for something like that.

[me6894]

Does it chug then die? Or does it just shut off like an electrical problem? Any codes?

[3800power]

You need a tuner to see what your car is doing man.

[RICH17]

I'd check all the vacuum lines, pcv, and EGR. Some of it may be clogged. And try to start it with throttle half open. Vacuum shouldnt be a problem on anything but idle in most cases.


And yes. Pick up a scanner

[nitehawkjcb]

There are no codes that are new, except a P0102, but I've been unplugging the MAF to see if the motor would stay running.

The motor starts, idles perfect, then just kind of dies. I'm fairly sure if I put some throttle to it, it would stay running a bit longer, but I'd rather not. If it can't idle on its own - like it's supposed to - then I won't attempt to force it to do so.

[me6894]

nitehawkjcb, on 05 March 2010 - 08:28 PM, said:

There are no codes that are new, except a P0102, but I've been unplugging the MAF to see if the motor would stay running.

The motor starts, idles perfect, then just kind of dies. I'm fairly sure if I put some throttle to it, it would stay running a bit longer, but I'd rather not. If it can't idle on its own - like it's supposed to - then I won't attempt to force it to do so.

Well try to force it once and see if it stays idling if you hold it at like 1500rpms.

If you have a maf code why not go to the junkyard and try a used maf sensor if you dont' wanna buy a new one?