Lil Beast

I could really use some help now. I've read a whole bunch of threads that are kinda similar to my problem but am still NOT able to figure this one out yet It's a 89 automatic, 4wheeler, 6 banger. As far as I can see, this thing has not been modified in any way, yet. When I got this rig about a year ago, it ran something butt ugly Did a ton of cleaning inside and out of motor, lots of Sea foam and pressure washing(my neighbors have finally forgiven me for smoking them out). It would start up with no problems until about three weeks ago. To start it I have to spray throttle body cleaner into throttle body and it fires right up. Runs really smooth and no problems WHEN it's running. It acts like its not getting fuel. I have changed the fuel filter and fuel pressure regulator( not cheap!). When starting, I can hear the fuel pump turn on and off. I have tried bypassing the ballast resister.I have read and tried the key jingle thing someone had talked about. I checked for spark and its a sparking good. I read the thread from Cruiser54 on refreshing grounds, AWESOME WRITE UPS DUDE, and did that. I am thinking about drilling/wallowing out the cps and reclean throttle body. I can't go out and buy parts right now because I was laid off back in september so money is extremely tight at the moment. I am new to jeeps and not afraid to modify anything or get dirty(being a hot rodder). I would greatly appreciate any help you guys could give me.

The Rooster

I see you have done your Renix homework great job on that... Now back to your problem... Check your fuel pressure with a mechanical fuel gauge and see if you are getting enough pressure at the rail...
Have you pulled out your injectors and check them yet... The Renix doesn't have the best injectors sadly...

Lil Beast

I thought about checking the fuel pressure briefly then promptly forgot about it. Big dummy I am. But I didn't think to check my injectors though. I will check fuel pressure this week but do injectors right now. It is Super Bowl Weekend after all.

Radi

I'd be tempted to pull an injector, set it in a glass jar and try to start. See if you have fuel.
Sounds like your injectors aren't firing until after the motor catches.
Does it crank at normal speed or a bit slow?

textherex

The root cause of this is simple. If you are using carb cleaner to start the truck then you are not getting enough fuel. If it runs, idles, and drives normal after starting then what you have an issue where the injectors are running lean. It might run fine but there is a window between lean and rich to where the engine is happy. I would be guessing that you are on lean side of it to where you can't get rich enough to start. Engines when cold use more fuel to warm up. So, then injectors might be clogged a little, sea foam works but only a small percent of it is left after going through the tank, lines, and filter. So I would suggest pulling them and cleaning them manually. Other thing, fuel pressure could be an issue to but you can find that at WOT and the engine stumbles because the pressure can't keep up with demand. Good luck and let us know what you find.

Lil Beast

cranks slow as usual.

Lil Beast

I know very little about injectors. I can pull them but don't know how to clean them Any ideas would be extremely helpful

The Rooster

I saw this on a website haven't tried it myself yet... im not sure i would use carb cleaner tho but the techron is good stuff... or if you have a u pull it junkyard by you get some 703 injectors from a 2.4 motor...

cleaned fuel injectors by taking them off and soaking them in Techron Fuel System cleaner. I rigged up a 9v battery with clip leads and an old doorbell switch. Puddled up a bit of cleaner on each end of the injector while clicking the switch momentarily and watching the cleaner get sucked inside the injector and drip out the other side. After doing this backwards and forwards a few times with each injector to make sure they were completely filled inside, I let them soak over night submerged in the Techron cleaner. The next day, I took them out and repeated the same process, but with carb cleaner back and forth through each injector. Reinstalled them right away and saw a major improvement at WOT on the test drive. This also solved a hard starting problem, which was why I was trying to clean them in the first place. I was worried about the carb cleaner possibly damaging something inside the injector, but have had no problems after six months driving this vehicle.

Lil Beast

I didn't get to looking at injectors today cause I was too busy yelling lots of bad words, when my little girl wasn't around me, at the tv. This "cleaning system" for lack of a better word sounds kinda scary but very doable. I am very intrigued. I have the batteries, wire, clips and a gallon bucket of carb cleaner(used for cleaning parts of course). I will make sometime this week to pull an injector first and check to see what I will need to do to make it happen, IF it's even feasible. Thank you for the info

Radi

Before you dig too deep into the injectors, pull one, stick it in a jar (to catch the gas), and watch it while someone cranks. You should have a nice consistent spray pattern. If you have drips, dribbles and spitting, either your injectors are clogging (clean per post above), or you have bad fuel pressure. Have you checked that, BTW?

davidap6

I have a '89, and I'm curious on how you can pull just 1 injector? Mine are all on a rail and have to be pulled at the same time.

cruiser54

Here's a thought since we're talking injectors here. I wouldn't waste any time trying to clean Renix injectors. They're prone to external leakage which can cause underhood fires. I would upgrade to the later style 4 hole injectors which "programbo" here on CF sells.

Fuel pressure test is a good idea.

The Rooster

He is correct on the Renix injectors they are junk... I was just trying to help you save some cash

cruiser54

Save him some cash and burn his Jeep to the ground? LOL.

The Rooster

Well he never mentioned that they were leaking lol...