Stroker running rich/rough

[Bouncy]

The list is long but I am looking for ideas I haven't thought of.

4.7 stroker
Replaced with NEW CPS, AEC, AIT sensors
Replaced with spare used TPS tested with analog ohm meter and has smooth curve.
O2 sensor new last fall
Map sensor...UNKNOWN but worked on last motor. Adjustable map sensor not installed YET. Have it on the bench right now.

Motor has 100 miles on it right now.

Drove it last night and it died 2 miles from home. I can smell fuel from the tail pipe. It wont start. Pulled plugs and their soaked with gas.

Fuel pressure gauge says about 20psi with key off and about 40 running.

Vacuum lines have all been checked.

throttle body is a stock with the bottom cleaned out from 55mm to 60mm all work below the throttle plate, and no light around the plate showing when closed.

Engine is running cold. About 170-180 on the temp gauge inside. Still have to hook up my external gauge yet. T-stat is 180 and hesco water pump with 3 core radiator CSF from dpgoffroad. Mech fan only right now...no need for the electric (manual switch) Two external tranny coolers. CSF tranny cooler used as power steering cooler.

So it drives for 2 miles, tranny is shifting really weird. 2nd gear by 5mph, 3rd by 20mph then lockup. Drags itself up to 30-35 then 4th kicks in with lockup. No kick down at all. I have adjusted the cable for pressure. I have checked the TPS settings about 12 times now literly and on 2 different sensors.

My cam shaft in the motor is Comp cams 68-232-4 xtreme 4x4 shaft for FI systems. Duration at .050 is 206intake 212exhaust with 113 degrees of separation. It was suggested that my map sensor is screwing up because of the cam not providing enough vacuum?????

I don't have an Air/Fuel gauge to find the 14.7 ratio yet. Waiting on a friend to help me with that. I also need to borrow a vac gauge from my buddy to see what its pulling.

Stats of jeep/motor
4.7 stroker
fully ported/polished head and TB (chambers polished to prevent detenation)
2.0 chevy intake valves 1.60 exhaust chevy
9.5:1 comp ratio measured head and block milled for flatness also
4.2 crank 4.2 rods
Fully balanced assembly
Pistons tops polished to prevent detenation
1999 intake ported
Mustang 24lbs injectors
1995 fuel rail with new injector seals.
APN header with 3" flange and 3" exhaust ceramic coated
MSD 40k volt coil
Livewires 10mm installed
Accel copper dist cap
Accel copper rotor
Champion copper plugs gapped to .045 (suggested from msd cause of the coil)

AW4 tranny from a 1995 (Unknown info other than I put new fluid in it with filter)
NP231 with SYE...not that it matters.

Oh yeah...The electrical before we jump there.
5-90s XJ kit. All power lines upgraded. All grounds cleaned up before being installed with new lines.
Only questionable line is a ground going from firewall to INTAKE bolt rather than the back stud for the head. I used ARP stud kit and ARP just doesn't get it that they studs need to match in length to the stock setup. So there wasn't room to install to back of head. Only to the top of the intake. Wondering if thats an issue or not..any ideas??

When the motor was running kinda good for the first 100 miles, it pulled strong. I burned through the CPS wire with the header....thus why it only has 100 miles. Since that happened, the list above of work to get this running again has taken place. Sensors all being replaced and such to get this back running and get the tranny issue figured out. Tranny issue has been present since day one of the stroker motor. Tranny shop wont look at it till I get the motor issues straightened out.

 

[Dr. Dyno]

It seems that you have fuel but no spark, so that would point to an ignition problem. Check if you're getting spark from the coil to the distributor.
You have an MSD coil so I suggest you swap a good OEM coil in and see if that solves the problem.

 

[Bouncy]

Forgot to add that info.

Spark is all good except when the plugs get soaked.

spark from the new MSD coil is very strong. Spark from each of the new livewire plug wire ends is good. And the plugs are new also.

 

[avnsteve]

plugs are getting soaked, too much fuel? try some stock injectors just to see? go back to basics, air/fuel/spark in proper quantities

 

[Bender]

I may be wrong but your running fuel pressure seems high. I think the 1995 used a 39 psi regulator which adjusts the pressure depending on the vacuum in the intake manifold. At idle the intake vacuum is high so the regulator should be lowering the fuel pressure to compensate so the fuel injectors are always seeing an approximate 39 psi pressure differential. I think I recall a reading of approx 30 psi at idle with a correctly functioning regulator. If you pull the vacuum line off the regulator at idle the pressure should jump to around 40.

If your regulator was stuck or wasn't getting a good vacuum signal your pressure differential at the injectors would be approx 49 psi at idle and 39 psi at W.O.T. That would change your fuel injector volumes from approx 27# at idle to the advertised 24# at WOT which may be hard for the computer to adjust for.


I could be wrong but it is something to check or research a little more on.

 

[Bouncy]

Thanks for the info.

I planed to get some help on the fuel pressure numbers this weekend. Hard to turn the key on while being under the hood to see what it goes to from zero to key on pressure...then watch for drops while sitting. etc.

I will have better fuel PSI numbers soon.

I was wondering if the vacuum might be a problem from the cam and throwing off the map sensor.

 

[jeeperjohn]

I think you need a larger vaccum reservoir or go back to stock 19lb mustang injectors.

 

[Bender]

Have you measured the vacuum?

If so, how many inches of Hg are you pulling at idle?

 

[Gojeep]

Also running a low thermostat will mean you are always running rich as the ECU is not reading the o2 sensor and leaning out the mixture until you hit 190-195*F.
Have you checked what codes are being thrown at all using the key on and off three times method? The instructions and the codes are on my site. www.go.jeep-xj.info