Hi there, I recently had my head gasket go in my 93 CX, I knew it was the head gasket, because I have been through this with other cars before... (saw the white smoke of death, smelled the sweet smell of burning rad fluid, etc). So, I decided to take on the job myself. Now I have been fixing cars and motors my whole life, but this was the first time I decided to go ahead and fix a head gasket problem...

The tear down and reassembly went relativity smooth- I took all known necessary precautions such as;

-checking the head with a straight edge for warpage. (none, and I never heated the car up above 3/4 on the needle)
-properly cleaning the mating surfaces with a razor and wire brush
-clamping the timing belt down and putting it back in exactly the same place on the flywheel.. not moving the bottom half of the engine at all.
-making sure all torquing was done in sequence and to the proper torque specifications
-I labeled everything and was sure not to get dirt into anywhere

But now I am having a problem with the car bogging when I give it any more then about a 1/4 throttle. It also blows tonnes of fuel out the exhaust! Its idling great, its starting everytime, we have run compression tests and it has good compression on all cylinders, its getting spark on all plugs, the timing in bang on, (although it goes out about 30 degrees when you give it gas)... I even took it to a mechanic and he said he doesnt know what is wrong... My next guess is that maybe the injectors somehow got warped during the install process.? I have included a video on my youtube channel to show exactly what its doing... ANY advice would be greatly appreciated. thanks in advance.

here is the video:

 

You have to put the ECU test jumper in while setting the spark timing. This is the same jumper used to read codes. Warm up the engine then stop it and put the jumper in. When you restart the CEL should light up steady-- meaning it's in test mode with no codes. If codes blink out, resolve them before going further.

In test mode the spark should stay right on the mark (center or advanced mark of the group of 3). In normal mode (no jumper), the ECU will vary it all over the place and you will end up setting it to a severe retard which will kill performance. The proper setting should land near the center of the adjustment range of the distributor. If it's all the way at one end, the cam is probably out of time.

Blowing gas out the exhaust could be an injector stuck open. Remove spark plugs and see if one is a lot different color from the others.

 

hmm, well I was not present when my mechanic did the testing, but I am almost 100% sure he would have known to conduct any timing tests in the proper mode on the ECU, (although I will run it by him tomorrow). He mentioned to me that he did get a code for an o2 sensor, which he thinks could not be the problem (he says because I never tampered with the o2 sensor at all)... does any of this make sense? He did, however replace the distributor cap for some reason, and claimed that the distributor cap was faulty, but I pulled it off and looked at it before hand and it looked alright. Either way the car is in the exact same condition I had it in before I took it in to get it timed and looked at by this mechanic minus him changing the distributor cap. Would you have any advice on how I could check this myself without a diagnostics machine? Seems like the mechanics around here want to charge me an arm and a leg with no outcome... Is there anything else it could be? the engine light code says its the o2 sensor, would the o2 sensor cause the car to bog down like that? Maybe one of them got moved around when I moved the exhaust manifold (?)

 

You just need a timing light not a big diagnostic machine. Check that the spark wires are on the distributor cap in order 1-3-4-2 going clockwise looking at the outside. Cylinder 1 is the one farthest from the distributor. Check that all 4 cylinders are firing by disconnecting the fuel injectors one at a time.

There is only one O2 sensor make sure it is plugged in and the wires have not been yanked out of the sensor body. Bad O2 sensor will not cause major driveability problems though.

 

Ok, so today I spoke with the mechanic, and yes he did time the vehicle with the jumpers set to test mode... so that rules that out, as far as I can tell, the timing is bang on, maybe advanced by a half a degree, but nothing the distributor adjustment wouldnt take care of in the long run. Here are some of the other things I tested tonight;

-sprayed soapy water all over the vacuum and fuel hoses... No leaks! so that rules out a possible vacuum hose problem
-pulled out injector wires individually and tested each cylinder... (all of them generated a negative response from the engine)... so that rules out the injectors.
-tested all spark plugs for spark... all good.
I am still getting a 2 second CEL light code when I turn the keys, which to the best of my knowledge indicates an o2 sensor problem. Next step is to grab a voltmeter and check the front o2 sensor for continuity. My only other possible explanation is that I did strip my front drivers side valve cover bolt, which also holds the ground wire in place. Yes I know I should replace this ASAP, but I have to wait for the weekend so that I can go and pull one from the wrecker's. Does anyone think that the disconnected ground wire may be tripping one of the sensors and giving the ECU a false reading? As far as I know, this ground is only for safety... I would be impressed if this resolved the issue. Thanks again for the input, Im sure I'll get to the bottom of this.

 

The CEL always comes on for 2 seconds when you turn the key on but don't start. That is to show that the bulb works. With the jumper out (normal operation), CEL staying on with the engine running indicates a problem.

The TPS and the MAP sensors have the same kind of plug. It is possible to reverse them and it will not run right. The plug with the solid white wire goes on the MAP.

Put the test jumper in and see if there are any codes.

Have you looked at the cam timing marks? You only need to take off the top cover to check.

 

ok, so I checked the o2 sensor and yes, its not working. this is the only code i get when i put in the jumper. the book says that the o2 sensor not working would cause a little difference in performance, but nothing like the problem I've got. aside from that, I borrowed a timing light and checked the timing with the jumper in place...

there are the 2 little timing marks on the crank pulley, then a third mark about an inch to the right of the 2. I marked the middle of the 2 marks with whiteout and put the gun on, and it appears to be timing properly until I give it gas, then the white mark moves down the pulley to the right about 20-30 degrees. is this normal? or should I expect that the timing mark stays within the cross hairs even when I crack the throttle? I checked the cam, and yes the marks are appear to be at TDC when the cam is at TDC. its all good that way, its just the timing still doesnt seem right to me. as soon as the engine starts bogging and the backpressure starts coming out of the air intake, the timing marks seem to be fluctuating. anyways, ive got another video uploaded to try and show whats going on when I put the light on it. its hard to see the mark at first, but you can see it move when I give it gas...

IMG 0866 - YouTube

 

You either need new o2 sensors or a distributor cap and rotor. I'd also get new wires and plugs, spend a good $100 on your car. Watch my video of my bogging problem and tell me if yours is the same. https://www.hondacivicforum.com/foru...problem-95543/

 

hmm, I put a new dist. cap and rotor on! it was the first thing I tried. this one is brand new. Im starting to think that maybe I warped or damaged one of the injectors. I also tried new plugs, new wires, checked all the plugs for spark.... nope. still doing it. its so weird, my last possible guess is to go get new injectors and an o2 sensor. Im going down to the store today, will post the results... thanks for the replys!