1990 Cherokee, auto 4.0 It starts when cold and drives. Will restart immediately but if let it sit for awhile it seems to flood/reeks of fuel and won't start and will backfire. Let it sit long enough it will start normally and be fine. I have done the following since buying it none running- CPS, Map Sensor, O2 Sensor, IAC solenoid, Cap,Plugs,Rotor Wires, Air and Fuel Filter, Starter, Ignition Switch, Refreshed Grounds and Added extra ground straps, Cleaned Throttle body and Air Intake Temp Sensor, B Latch, Fuel, and O2 Heat Relays. Any ideas would be greatly appreciated...

 

Leaky injectors can cause your problem. as in you shut it off but the injectors don't all close. Floods the engine. Wait long enough and the fuel evaporates and it starts. Usually with a long crank time.

I suggest replacing those crappy injectors with teh later style 4 hole types for a coupla reasons. One is they don't leak at the seams unexpectedly like yours do and the other is it will probably solve your problem.

 

^^^ i second that...and i would do it sooner than later.

 

Exactly what they said. Replace your injectors.

 

How can you get the four hole injectors? The precisionautoinjectors.com website only shows four hole injectors for 99 and up jeeps, they look much longer then the orginal Siemen injectors. Is there a way to get the better injectors in a Renix motor?

 

Contact Programbo here on CF for injectors. He knows which ones to get and he has them. Don't get used ones from the junkyard.

www.precisionautoinjectors.com can help you also.

 

Ok thanks. I was also looking at New Lucas Injectors i found at Five-0 Motorsports....
http://www.fiveomotorsport.com/fuel-.../jeep/?v=18020

 

That's $240. Kinda pricey.

 

Yeah it is but still cheaper then rockauto.com or the parts houses. I found much cheaper on ebay but have concerns on quality and service if they are junk....

 

Contact Programbo or Precision then.

 

Will do, hopefully this will fix last obstacle to driving it !

 

Replaced the injectors and fuel pressure regulator. Still wouldnt start. Took out a plug and laid it on the valve cover. It sparked when cranked. While cranking fuel ran out the empty hole and appeared the engine was flooding out. Ohmed out the air and coolant temp sensors. Coolant temp sensor was way high for the temps so I replaced it. But still doing the same thing. The Map sensor and o2 sensor are new.. What else could be the problem causing it to dump too much fuel?

 

all cylinders pour fuel out ?

 

I didnt pull all the plugs but the three i did where all wet with fuel.

 

i didnt pull all the plugs the three I did were wet with fuel..