I dont think i will get to put injectors in until monday. If they dont get here tomorrow. Postoffice on campus is a day late and they dont deliever mail on saturdays.

 

I guess I'll never do that then haha

 

yea our jeeps are not suppose to be a powerhouse

 

Unless you drop a built Chevy motor in it

 

I honestly would drop a cummins in there If i could drop anything. After that I like 4.7 in My grand cherokee.

 

eh, I will say that I love me some cummins turbo diesel power but those are wayyy to heavy for an XJ, If I were building an old F250 or something you'd better believe I'd drop one in for a power plant

 

I would have to say LS1 with supporting drive train for the win. It would be fun to have a 14sec, maybe 13sec, 1/4mile cherokee on 33" tires.

 

Well got the ford injectors in.

and it still idles the same. It seems like there is a better throttle response with them and it seems to get into the rpms faster, but it didnt fix my problems. I bought some b12 and when the motor cools back down I am going to go out and spray it around my intake gasket and throttle body to see if they are letting air in around them.

 

well sprayed the b12 around all the gaskets I could think of and It didnt do anything. No surges no nothing.

 

Have you tried testing any sensors? from what you've done so far it sounds like thats the only thing left. This might be a long shot, but it sounds like your Jeep is getting stuck in open loop mode and thus is dumping ridiculous amounts of fuel into the engine. Its possible you have a bad O2 sensor that the ECM isn't detecting. I'd just go through all the sensors that could throw off your air/fuel ratio and don't put the new cat on till you fix it. check your TPS, MAP, coolant temp, Intake air temp, and O2 sensors...all you need to do so is a hayne's manual and a multi-meter. if you don't have a multi-meter places like harbor freight carry them for like $4

 

^^ Agreed. Just going to be a major PITA. I know where to get a Facorty Service manual if that will help. Just let me know.

 

A FSM? I would much like to have one of those

 

I've heard the Bosch Gen III are proven performers. Better spray pattern than the older models and OEMs. Looking at their site for info and pricing, there are two models for the XJ 4.0 blue and orange. I'm too much a newb at this engine to know the difference in the series, but it seems that we should see some kind of mileage increase with the new gen injectors.

My 92 has 107K on the original motor. Its a DD for my business and sees 250 miles a week on stock sized tires/wheels. Been through the regular replacement stuff, plugs-points-condenser, cat is good, 02 sensor, syn oil in the drivetrain, wheel alignment, new steering box and two seafoam treatments. If she gets out on the open road its 18-20 mpg. Around town, up and down hills getting 14-15 like clockwork.

My last hope is that the new injectors may hold the key to mileage nirvana......


.

 

I read somewhere you can use 1995 Dodge Neon injectors and see a mileage boost. I will have to find it.

 

The neon injectors are in the thread i pasted earlier on. Mine are the bosch gen 3's
Took to the mechanic yesterday and they said all sensors are fine. I have changed all the o2's already for brand new ones. I just dumped 3 cans of seafoam through the intake because mechanic said either carbon build up or the comp is messing up slightly. So i cleaned the valves and nothing changed. Tomorrow I will do a leak down and compression test. JY wants 85$ for the ecu and it is a as is thing so it that doesnt fix it then tuff luck. When I can get it home I will replace the cat with my high flow cat. I would do it here but it is shorter and it doesnt have the o2 sensor hole built in it.