99+ intake swap from hell; I need some help

Ok so when I first started this project I was guessing 5-7 hours. Now I'm at 17 hrs and a major block.....

I did the intake swap and ran into some problems with the 99+ injectors found here http://www.naxja.org/forum/showthread.php?t=912384 .

So I decided to swap the injectors out, however something came up and I had to leave my XJ at the garage for the week untill yesterday. During the week I bought some NEW 24lb injectorsnfiguring all these fee flow mods(6x9 cone filter 60mm TB, 62mm TB Spacer, Intake manifold, Free flowing exhuast) were going to make my engine run a bit too lean. The injector swap went nicely I hooked everything up and.................nothing. So we did some poking around and found that a fuse had some how come loose then it started. We checked the codes and found everything was good. With our accomplishment we went to grab some food. When we came back we changed the oil.

I disconnect the battery and hold the key for about 30 seconds. I reconnect everything then I start it up and take it for a drive around the garage to make sure everything is ok. While I'm driving my friend had a OBDII scanner hooked up to check if everything was good. After 10 min of average driving we decide everthing is good and I drop him off at his car and we begin to drive home.

About 5 min out my while I push on the gas I notice no response, I looked down at my Tach and see the needle flying around like it was on crack. :looney: Luckly I was able to pull off the main road and glide to a parking spot. When we tried to start it it the neddle would do it's crazy thing, and sounded like it was turning over but something was stoping it from doing so.:dunno: On third start attempt the only thing going was the starter. I inspected the ground/undercarrage and found no leaks. So if someone could help me out that would be great cuz right now i feel like this guy....

anyone?

Sounds like its running far too rich.

It's symptoms almost sound like a stuck choke on a carbureted engine that doesn't open up once the engine gets warm.

Did your crank sensor wiring get burnt on the exhaust or get caught between the manifolds and the head? Sounds like it might be something along those lines considering what the tachometer is doing.

Hmmmm...That seems that could be it, can u post a pic of it and where it's located so I can check it out. Thanks

I'm sure it's running rich but I don't think it'd runnning THAT rich, on a stuck choke the engine usually craps out at around a min. I was driving fine for about 15 min.

You have done lots of mods but 24 lb/hr injectors are what a lot of people use for their stroker engines.

A 4.0 shouldn't need that much fuel.

I'm going to put a diode on the MAP sensor so It doesn't run as rich.

The CPS bolts into a slot in the bellhousing on the driver's side near the top and pugs into the same wiring harness that's used for the TB sensors.

Fwiw, as part of an engine rebuild I added a 99 intake to a 96 along with the bored TB. I reused all the same sensors from the 96 on the new TB and also re-used the 96 fuel rail and injectors. Thought about using the 99 injectors that came with the intake as they're supposed to produce a finer spray but in the end decided I'd changed enough things by this point.
Also, Doctor D's tech spec page here:
http://www.jeep4.0performance.4mg.com/tech_specs.html
indicates the 96-98 injectors are already 23.2 lb/hr which is pretty close to the often referenced Ford ones. Runs fine after about 120 miles.

Ok so I checked the CPS and it's all nice and ok, the fuel line is getting pressure, I checked the whole ignition system and it's good, I am at a loss here.....

Grounds? I've seen tachs doing crazy things, full sweeps or bouncing around. It's usually related to low voltage or grounds loose. This'll also keep your engine computer from doing its job.

I did a pretty complete sweep of the engine bay for loose wires. Found a few that had to be put into place but made no head way. Now I just have the engine not starting. I'm almost consitering taking it to a place to get it checked out, because I can only have the jeep down for so long.(I'm only 17 and still in HS)

BTW I can't find the MAP sensor on my 96 XJ SE. I'm just courious because it isn't in the location that was shown on go-jeeps page.

On a 96 the MAP sensor is mounted to the TB, not on the firewall as shown on Go-Jeep's site(he's got a 95.)

couldn't find a better picture than this page from JP magazine. The MAP sensor is the rectangular black box at the bottom of the picture with the wires attaching on the left of the box. It's mounted to the TB and connects to a port on the TB via a short bit of hose.

http://www.jpmagazine.com/techarticles/154_0412_jeep_4_0l_power_testing/photo_07.html

Don't have any ideas on the non starting issue. Spark, fuel, air, right? Have you verified the coil wire's on? Getting spark at the plugs? You haven't moved the distributor in all this have you?

Also adding a diode will do nothing to your Map sensor. A diode is like a one way valve for electricity. It will only allow current to flow in one direction.

The diode was just an idea, however I don't think the too rich thing is the issuse. When I go down there I'm going to use some "starter fluid" like gas and just spray it down my intake manifold while i try to start it. If it starts then I know it's a fuel issue if it doesn't then i know it's the ignition system. Sound good?

What year is your XJ? Nevermind found out in the other thread. What psi is the fuel rail regestering?

I have no idea, how can I find that out, with a OBDII scanner?

No, you need to use a fuel pressure gauge.