I recently had a bad head gasket.

I replaced with fresh cylinder head. Changed out the water pump/timing belt/tensioner, intake/exhaust/valve cover/spark plug/cam gaskets, did a fresh tune-up (dizzy cap, rotor, plugs, wires), headgasket, head bolts, valve adjustment. AKA $$$ invested. Ignition and mechanical timing is spot on.

After I got it running I had a code 6 pop up, everything was the same from the previous head except the coolant temp sensor, switched it out and cleaned the plug. I reset the ecu and it hasn't came back.


Problem (loss of power, stuttering):
Car hits 3k when cold and sill start sputtering, after it is warmed up it will only go to 2k rpms at the most, but when I'm going up a hill it will go to 1.5k rpms and no more. Speed starts lowering making it impossible to make it up a minute hill.

IF I rev the car in neutral it will go to 3k rpms, but it'll only hold it for a second or so and then it'll start dropping down to 1.5k rpms or less.

Car starts every time, holds the idle fine. It is driving at 25mpg compared to 42mpg it was getting right before this started happening!!

The car has very minimal smoke coming out of it. No leaks from anything (that I can see).

A little stuck on what some of these could be. Hopefully someone can share some thoughts of what to check. I don't have a pressure tester to use on the radiator system (which sucks).


Thanks for any and all input!


***Things I have done so far to figure out the codeless lack of power***

Replaced fuel filter new
Replaced spark plugs new
Replaced distributor/cap/rotor/wires with known working dizzy
Replaced catalytic converter with spare, but car has 2 and haven't touched the 2nd one
Replaced leaky fuel injector with spare
Replaced FPR with spare, o-ring may need to be replaced
Added fresh fuel from a different gas station
Added Gumout fuel injector cleaner
Checked mechanical timing (cam timing), it was good
Checked ignition timing, it was good
Checked compression and it was 180psi across
Air filter is newer

Replaced oxygen sensor with known working o2 sensor, threw code 1

 

I'd check out the other cat. Might be plugged up.

 

i think it might be a bad ecu- check this out https://honda-tech.com/forums/honda-crx-ef-civic-1988-1991-3/%5Bfaq%5D-ecu-codes-trouble-shooting-468260/

 

Before I get too involved check 2 things - your MAP sensor is hooked up (vacuum), and pull the O2 sensor out and see if the situation improves.

 

Might also be leaking spark plug wires.

 

Could be EGR valve/system... could be a lot of things really.

 

Checked EGR by taking off the vacuum hose, no difference.
Replaced ECU with known good one, no difference.


BUT I did have a break through today, pulled the o2 sensor and drove it around. I had power!!

So I took it to a muffler shop, but they wouldn't touch my 2nd catalytic converter even though it showed in their parts book the HF didn't come with them. (they were saying they did and were showing me the SI model).

Parts stores don't have until next week. I'm going to try and put something together to get me by for the time being.

 

reading this makes me wonder, how do you know if you should really replace the o2 sensor? I mean if there is no code but engine feels weird sometimes. Don't mean to thread jack..

 

Obviously you figured it out - most likely the blown headgasket caused the catalytic converter to clog.

Also, that's not an efficient way to test the EGR. You must apply vacuum to the EGR valve and see if there is a difference. If there isn't then that's your problem. Also, the ports could clog as well - not necissarily that the EGR is bad itself...

 

Obviously either a code thrown or you can check it with a multimeter. If you didn't mean to thread jack then why did you post an unrelated question in some one other than your owns thread? You can make your own thread by pressing the "New Topic" button.

 

because people would then bitch and say that we have a thread somewhat related to this here ___...that is why. Then if I didn't say that, I knew you would say that I am thread jacking. Can't please you eh? Oh well...

Anyways thanks for the information.

 

Yeah that was my conclusion. I never dug too much into the EGR, I tested that and when I did the EGR CEL came on. Left it at that.

I'm all too familiar with clogged EGR ports, I've redid the ports on Crx's twice and it's not that simple a closed/sealed system.


After no luck with the muffler shops, I will be trying to put together an exhaust tomorrow.

 

Good deal.

 

Cut out the 2nd catalytic converter and put a straight pipe in.

Loss of power, solved!!!!


The catalytic converter was melted on the outlet side and it appeared broken in half. The resonator had a sound in it like it was loose. So as soon as I can I plan to switch out the mid-pipe and axle back since previous owner didn't do a good welding job and looks like crap.

 

Not to be full of myself (even though I am ), you are welcome and I am glad to see you figured it out.

 

Straight pipe ftw!!!

 

who needs a cat any way