I have a 2005 Suzuki Forenza Wagon - 2.0L L4.
First off I apologize for the TL;DR.
In the beginning there was only a slight problem with heating, It would never get as hot as I always thought it should get. But it did get hot enough so I ignored it as the ignorant frequently do.
Then I began noticing a slight misfire every once in a while and only when I first turn on the engine. So, having never done the Plugs and wires on this car, I decide to take care of it. Ordered the parts and waited for them to come in.
As I was waiting, the engine began overheating all of a sudden, seeing this now, I deduced that my thermostat must be gone, and before when it was only slightly hot it was broken in the slightly open position, and something happened, and now it was closed and began my over heating problem.
So I ventured to replace my thermostat, and long story short, I have to get one off eBay. So I am currently waiting for that one to come in.
The wires came in so I got the plugs and set out to replace the whole set.
After I replaced the plugs and wires, the misfire became vividly more apparent. highly noticeable. I double checked the firing order and that was all correct. I made sure they contacted the coil pack and each wire was getting spark from the coil, and it was. very strong. I pulled the plugs and wires, and double checked that the plugs themselves were still OK, and they were.
So, Having eliminated spark, I moved on to fuel, I decided to pull the fuel injector connectors one at a time while the engine was running.
only one fuel injector did not effect the engine, the other 3 I barely had it off before the engine began to stutter and shut down.
Cylinder 2 Fuel Injector.
I Have another Fuel Injector on order, and while I was waiting, I tried throwing in some Fuel Injector Cleaner and try out the coolant issue, perhaps running the engine would work a blockage free, so far it has not.
My main problem that I have noticed, when I put the radiator cap back on the coolant reservoir when the pressure builds up, either the misfire starts back up, or it gets more pronounced. I don’t understand how the two correlate.
I am probably over thinking it, but What I was thinking is maybe the thermostat being closed was not allowing fluid through, and so the water pump couldn’t push the coolant freely, so it would bog down and maybe stretch the timing belt slightly, enough to adjust the timing and cause the Cylinder 2 Misfire.
I realize it’s kind of a “Rube Goldberg” explanation, but there it is.
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