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Car running on 3 cylinders.

AlaskanDsm

Proven Member
1,122
12
Oct 21, 2007
Fairbanks, Alaska
Hey guys. I am need some guidance.

Here is the deal. Yesterday I was sitting in my car in front of a hotel while my friend who was visiting was checking on prices. Well during that time, the car went from idling fine down to 3 cylinders... sounded like a Subaru. Well I had that happen one time before. Well anyways within about 30 seconds, the engine idled back to normal. so I shut it down thinking WTF.

Anyways, My friend decided not to stay at that hotel but a different one. The car ran fine the whole time. After i had dropped her off and helped her carry her bags in, I said my goodbye and went to drive home. Car started fine, rolled out of the parking lot fine, but once I got on the road to get onto the freeway, the car dropped a cylinder again and I thought that the whole car was going to shake apart from the vibrations. Anyways, I pull over and take a look at the engine. Can't see anything wrong. Well I had to get the car home so I drove it on 3 cylinders. long ride.

Well I got it to Autozone thinking that maybe one of the plug wires or spark plugs had gone bad. Swapped them both out and it is still only running on three cylinders.

What do I do??

When I get home tonight, I will attempt to verify timing although because the problem rectified itself the first time, I do not believe it is timing.

Second, I don't believe that it is a coil pack because the car isn't running on 2 cylinders. And for the same reason, I do not believe that it is the transistor.

Third, it could be an injector... I am going to go home and check by running the car and unplugging the injectors one by one and see if it causes a difference in the idle... may also at least identify the bad cylinder. I can check for spark at that time by using one of the old spark plus against a bolt or something.

Is there anything else that I am missing or misleading myself to believe? Any help would be really appreciated!!!

Attached is a video below for reference to the sound of the car.
<iframe width="560" height="315" src="http://www.youtube.com/embed/AkDx4rpEq-k" frameborder="0" allowfullscreen></iframe>
 

AlaskanDsm

Proven Member
1,122
12
Oct 21, 2007
Fairbanks, Alaska
Yea I think that I will try and find the misfire by unplugging the injectors. Once I find that one, I will test for spark first. Once I verify spark, I will check for compression at the cylinder. IF both look good then I believe It could only be the injector or electrical to the injector.
 

TAL0NTSi

Proven Member
161
0
Dec 26, 2010
Westerville, Ohio
I just ran into this exact issue and it turned out to be a bad injector. I determined this removing the connectors on the injectors one by one while the vehicle was running. (obviously, use caution when dealing with anything fuel related) If when you unplug one of the injectors, and the idle stays the same, you should have it narrowed down. Hopefully that helps a little.


EDIT: I'm sorry, I submitted this post right after you said how you would check for the misfire. Either way, that was my issue and a new injector fixed it!
 

AlaskanDsm

Proven Member
1,122
12
Oct 21, 2007
Fairbanks, Alaska
Haha. That is awesome that we were on the same mindset. But I appreciate the information anyways. I have just had a bad luck streak lately with my car and I have a full set of 660's that I have been too lazy to install sooooooooooooo this might just be the time that they get installed LOL.
 

TSi Kid

Proven Member
1,476
11
Mar 12, 2010
Avondale, Arizona
Check the resistor pack. If it's bad it'll stop the power from going to the injector and do the same thing. I had it happen on cylinders 3 & 4.
 

AlaskanDsm

Proven Member
1,122
12
Oct 21, 2007
Fairbanks, Alaska
Just to clarify, when you are talking about the resistor pack, you are talking about the transistor that provides the coil pack with power correct? Or is there some other resistor pack that I am unaware of.

And maybe I am mistaken (has happened before) but I thought that most issues related to the coil pack/transistor usually cause problems in 2's due to the nature of the design. If this is not correct thinking, PLEASE correct me so I understand better.

***UPDATE***

So after worK I came home to trouble shoot the problem. I grab my tools, lug them all down to my car (apartment complex), and I go to start the car and... Ska-douche... starts and runs fine... my first thought wasn't YAAAAY! it was WHYYYYYYY?!?!?! haha. Anyways, took me about 30 minutes to replicate the problem before I could try to diagnose it. I kept having issues driving it around for 25 minutes with it randomly misfiring and dropping to 3 cylinders for 5 seconds and then coming back. But it would operate fine under idle, normal driving, and even WOT. instead, it would randomly have an issue. Well the more I drove it the worse it got so I brought it back to my apartment... let it idle for about 10 minutes and then like magic, it dropped a cylinder.

So now I try to troubleshoot the problem. I realize that taking the clips off a hot injector was going to suck so instead, I grabbed a small screwdriver and touched the top of each one of the injectors for a slight knock feel in the screwdriver. Well I found that #4 had barely any feel to it. I kill the engine, unplugged sparkplug 4, restart the car, and it ran on 3 cylinders.

My assumption currently is that the injector is on it's way out and needs to be replaced. Lucky for me, I happened to already have a set of 660's that I have been waiting to put in. I am going to install these over the weekend and continue testing... and tuning for them haha. I will post additional results here and resolve once the car runs normal.
 
Last edited:

DROOPY209

Proven Member
493
4
Jun 23, 2004
NorCal, California
I just had this issue with my car. I had good spark on all 4 cylinders. The injector on cylinder #1 went out. When the car was cold, it would run just fine. After about 30 min or so, it would start to miss a beat randomly. Then it would run on 3 cylinders. A few min after I would get a check engine light. Once I narrowed it down to the correct injector and disconnected the injector plug. I got a 9V battery and some mini alligator clips and hooked it up to the injector. Polarity doesnt matter, just short taps when you make contact with the injector. You should feel a ticking if the injector is working. My injector would not work once I had been driving around for a while, but if I let it cool down, it would run fine.
 

pauleyman

DSM Wiseman
6,906
1,944
Nov 19, 2011
oklahoma city, Oklahoma
perhaps check the coil pack aswell?

Op already stated he didn't think that was it because if it were a coil it would drop two cylinders. Only way it would drop one is if maybe the tower on one cylinder was cracked. For what it's worth a datalogger will drop a cylinder at a time for you. Way easier to find a misfire.
 

cliffkemp

Proven Member
391
11
Apr 19, 2010
carrollton, Georgia
I had a similar issue and found out it was the injector connector itself. It had a little bit of corrosion on it. I cleaned the connector and plugged the injector back in and, it has been running good since then. This may be the problem as well. I would check both ends of the connection to the injector as it was the issue I had with the same cylinder/injector, too. Hope it is fixed now and you changed to the new injectors as well.
 

AlaskanDsm

Proven Member
1,122
12
Oct 21, 2007
Fairbanks, Alaska
So I am not completely satisfied at the moment that the problem has been solved but it may just be for a lack of tuning on the new 660's. the ECU is set for the 660's but has not been tuned. I am still getting misfires and such and I think I am a bit sketchy on driving the car more than a few miles haha. But I will try to get some of this sorted out but the initial results are that I had a bad injector on cylinder 4.
 
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