michael.pang

I was driving over 100 km/hr at 4th or 5th gear, however I accidentally shifted down to second gear (this cased immediate engine braking to match engine with gear). I thought it was way to hard on my engine or transmission to drive at such high speed at gear two because the kickback (engine braking) was extremely strong. I resumed driving. When I got off the highway and came to a complete stop, my engine would die on idle. I started it back up but I needed some gas. Now, in order to start the car, I need to add gas and keep my foot on the pedal slightly to keep engine running at idle. Sometimes the engine stays on 1000 RPM while on idle, but when I drive it it will frequently stall when my RPM drops under 1000. There is no check engine light, however I rev'd the engine to make the light appear, I plugged in my OBD II and it says cylinder #2 misfire. What could be the problem. Any advice would be appreciated.

ezone

How high did the RPM go when you mis-shifted? How far past redline?

Do a compression test first.

michael.pang

Hi ezone,

I really appreciate your help. Thank you for your response.

When I mis-shifted my RPM hit the highest mark possible.
I did a compression test today and it read 125 PSI on all four cylinders.
I changed all the ignition coils and spark plugs (so this should not be the problem) however, after driving it for a bit, I took the spark plug out of the cylinder that isn't firing and my spark plug tip turned black.

I have a feeling its electrical related or the fuel injectors, how should I diagnose this?

Thank you, for you help once again.


Michael

ezone

On a K engine, if you keep counting lines on the tach that's something like 10,000 RPM?

I was guessing you floated the valves and bent a few.

125 is super low IMO. Either your test method isn't what I use or your equipment is off. I expect minimum 200 PSI on an engine like that using my tester and my method.


If someone took the check valve out of the tester hose and screwed in a Schrader valve from a regular tire (they LOOK the same), the tester reads about half of what it should.



Pull all plugs out and stick a battery charger on to keep cranking speed consistent.
Install tester so you can see the gauge.
Prop the throttle wide open.
Crank it and keep cranking it until the gauge stops climbing, then let it hit a few more times just to make sure that's all it's going to climb.
Repeat for all cylinders.

Even if the gauge is wrong, that should show if there is a difference between cylinders....I hope.

Compare with another engine or another tester.
If compression really is confirmed to be that low, I'd do a leakdown test next to see where the leakage is going.