Civic vaccum leak or bad engine swap?

[curvy95honda]

Blew the engine in my 95 coupe and headed to get a replacement. The most inexpensive option is the JDM version which is right around $600 just for the parts. The wrench who I consulted about the swap, pretty much took care of the entire swap. Drove the car home a few days later.

After driving the car for a few days I noticed there wasn't as much power as there used to be. When I step on the gas, my car kinda slugs along then kicks in and delivers the goods at around 4000 r's. I don't really notice it using normal driving but, when I am in a hurry, I really notice it because my car just doesn't move like it used to. Nothing mechanically wrong, in other words, this problem is not stopping the car, it just doesn't act right.

All of this was a year ago, at this point, the car has been getting progressively worse and is now shuttering and shaking so bad, I can't even take it on the freeway. Accelerating for that matter makes the car stammer and shutter; just really, really bad on the freeway.

Now, I am frustrated. I have taken the car to Honda, local mechanics, transmission shops and close family friends, including the wrench who did the transplant. No Help! I have got everything from replace the o2 sensor to the battery is bad. I have replaced tons of parts on this car and am now exhausted from this fiasco.

I have narrowed the problems down to two possibilities.

1. The original engine that came with the car was swapped and the new engine doesn't carry the same code as the previous engine. A D16Z6 is the apparent choice for this car (at least the 1.6l option is the only one Honda will give me when I enter my vin# to search for parts) however, the transplanted engine is now a D15B. The ECU doesn't seem to be replaced as the dust on the unit looks about 20 years old… Does this even matter? If the wrench swapped out my D16Z6 with the JDM D15B, would I even need to use the JDM ECU, to accompany the new engine? Would this be the cause of my problem?

2. So, in researching other problems that are happening with the car, one of them being the fact that my cruise control suddenly stopped working, one of the troubleshooting tips in the Chilton book was the possibility of a vacuum leak. Since my car is totally incapacitated now, I am adamantly researching this problem and I run across a generic online troubleshooter for car problems. After I told the troubleshooter what was going on with my car (as I stated above), it said "have a mechanic check for vacuum leaks". Could this be the source of my problem?

My question is: Which one is it or is it even any of these options? I've been at this for two days straight now and can't seem to find anything on the subject. Any help or insight would be appreciated.

[DownToGround]

lets try and give ya somethin.. the map has a vacuum line going to it, and if that was in correctly hooked up it would make the car run bad, or if there is a break in the line.. also have someone put a timing light on it for you, make sure its in time. as for the 1.5 vs 1.6 it shouldnt be a big deal as long as they used your z6 parts to build the d15 long block. the map vacuum goes to the top right of the throttle body.

[curvy95honda]

wow, you have given me more to work with than any friggin' wrench has so far, thank you... The MAP sensor is mounted to the top of my throttle body. There is only one tube coming in or out and it looks like it goes to an AC canister of some kind located on the firewall. I took the hose off and nothing happened. That's strange, i would have thought it would have at least changed idle while i took that hose off??? The hose appears to be relatively new though. It is one of the better hoses on the vehicle. No cracks or leaks in that hose. do you suppose my MAP sensor is out?

[danielsatur]

Try doing a smoke test, do a google ''Youtube Auto smoke test''

[curvy95honda]

I guess i could order a "smoke machine" on eBay as i am fresh out. there are 21 different emissions controls on this vacuum circuit so, that should be better than replacing all 21 parts. Certainly beats the soap test... I am hopeful that i will find it though before the snail mail can deliver me a new smoke machine so, i will try a few more things before i go orering any new equipment. Thank you

[curvy95honda]

To add, my AC hasn't worked since the swap. The compressor runs when i turn the car on but, no cold air. All of the lines appear to be intact so, i dont think the wrench omitted putting any lines on. I have since refilled it with freon but to no avail. Also, the Cruise control suddenl;y stopped working about 6 months ago, would that be a symptom?

[danielsatur]

Redneck smoke Test!
1) Remove the air filter
2) Put plastic wrap around the air filter for blockage.
3) Install the air filter, you don't want smoke coming out of the air box during test.
4) Disconnect the air vacuum hose to the brake booster.
5) Light a Black + Mild cigar, and hold smoke!
6) Slowly blow smoke into the intake booster hose, and plug hose with thumb.
7) Watch for smoke leaks.

Don't forget to remove the plastic on your air filter when the test is compete.

[curvy95honda]

that's hilarious 'cuz i was just thinking of how i could pull that off. My stepfather has a fog machine for halloween, maybe ill try the cigar and if that doesn't work, ill try the fog machine. Thanks again.

[danielsatur]

How about a mini shop vac + smoke bomb in reverse!

LOL - How about a Pot head, he could find the leak!

[curvy95honda]

Originally Posted by DownToGround

lets try and give ya somethin.. the map has a vacuum line going to it, and if that was in correctly hooked up it would make the car run bad, or if there is a break in the line.. also have someone put a timing light on it for you, make sure its in time. as for the 1.5 vs 1.6 it shouldnt be a big deal as long as they used your z6 parts to build the d15 long block. the map vacuum goes to the top right of the throttle body.

To tell the truth, I don't believe that the mechanic who swapped the engines used any of my Z6 parts. I can't tell though. I do have another Civic identical to this car. It's a 95 coupe EX just like my car. It has the original engine in it and the parts do not look the same. It's too difficult for me to tell which of these parts are from the original engine but, I can plainly see that the throttle body canister on this Civic is not the same one as my other Civic's. This one is dull and does not look good. The canister in my other civic is shiny and looks cool. Is there some way of testing this? Can i just go buy a D15B ECU?

In driving the car with a close family member, we have isolated that the problem only appears under load. In other words, when my car is pushing to go up a hill, it will not accelerate. turn around and come down the same hill I went up, no problems at all. It seems like the vtec is not getting the chance to kick in. It doesn't even want to shift going up the hill. Were not talking about a really steep grade, simply a load. if I have enough weight in my car where momentum will not get me moving, the car loads up and slugs along. Any more suggestions would be greatly appreciated.

[DownToGround]

the vacuum line on top of throttle body is emissions no biggy.. sounds like its timing related. i would put a timing light on it.