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-   -   first 3 cylinders not firing after cleaning injectors (https://www.cherokeeforum.com/f2/first-3-cylinders-not-firing-after-cleaning-injectors-198783/)

88witha96 Sep 5, 2014 01:14 PM

first 3 cylinders not firing after cleaning injectors
 
I was having issues with my fuel pump a few days ago so I pulled the tank and found it full of rust. I replaced the tank and fuel pump added a can of seafoam to a full tank of gas and it ran good for about 3/4 of that tank. Then it started having trouble accelerating again. I thought maybe the injectors had gotten clogged with the rusty fuel so I took out all the injectors and cleaned and tested each one and reinstalled them. Now the first three cylinders won't fire. I have metered the injectors, I can hear the each injector actuating. I checked the spark plugs (swapped with other working cylindrers) I can't figure out what is causing this. Please help! Thanks

88witha96 Sep 5, 2014 01:43 PM

I do have a spark at each plug. I even got zapped a couple of times. What else could I check?

7ate9 Sep 5, 2014 01:56 PM

All your vacuum lines are good?stupid question but it happens .

88witha96 Sep 5, 2014 02:27 PM

There was a kink in the vac line! I staightend it but still no change in the 3 cylinders. Its starting to sound a little rough and white smoke from the exhaust. Maybe from the injector cleaner?

88witha96 Sep 5, 2014 02:30 PM

Could that kinked vac line have caused permant damage to the cylinders?

88witha96 Sep 5, 2014 03:07 PM

I have to floor the petal to get it to start. Do I need to bleed the fuel lines after cleaning the injectors and fuel rail?

Trey Sep 5, 2014 05:08 PM

I would remove the rail and all the injectors. get a seal kit for the injectors before you do this. there is a good chance that 1 or more might get damaged. turn each injector upside down and tap it on a towel. the injectors have a small screen at the inlet and could be plugged up with debris. flush the rail as well once all the injectors are out. if you use a little oil on the upper O ring seal you will have less chance of damaging them when you re install.

Trey Sep 5, 2014 05:11 PM

the kinked line would not cause damage. you may want to make sure it did not get a small tare in it.

88witha96 Sep 5, 2014 06:29 PM

I installed all new o-rings on the injecters. I flushed all the injectors and the rail. I tested each injector and saw that each one was spraying fuel before reinstalling. All the vacuume lines are good now. I even pulled each hose and blew through them to make sure they weren't clogged.

88witha96 Sep 5, 2014 06:40 PM

Here is a video of how I cleaned the injectors using a battery and carb cleaner.
www.youtube.com/watch?v=7aT4S1lIBAY

cruiser54 Sep 6, 2014 09:04 AM

1 Attachment(s)
Did you screw up the TB to MAP hose in the process? If so, it will run pig-rich because the MAP sees low vacuum and tells the ECU to open the injectors for a long pulse.

88witha96 Sep 6, 2014 10:26 AM

Just did a compression test,
Cylinder 1 140
2 135
3 145
4 135
5 132
6 132

salad Sep 6, 2014 11:39 AM

How exactly did you determine that the first three cylinders aren't working?

You sure the injector wires are in the correct order?

Kalali Sep 6, 2014 01:57 PM

White smoke is most likely from the Seafoam.

88witha96 Sep 6, 2014 02:55 PM

Determined cylinders werent firing by unplugging spark plug wires one at a time and no change in engine sound for the first three.

I labeled the injectors and I'm sure they are in the correct order.

Just replaced the map sensor and hose just to be sure, still no change. Do I need to disconnect the battery for thirty minutes to reset computer, because just tested cylinders again and still not working.

I took off the cylinder cover a minute ago to see if any obvious damage, but everything looked okay.

Any other suggestions? Maybe the throttle position sensor or the crank position sensor?


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