Issue after ls swap

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lswhitecivic

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Motor is a 94 B18b, car is a 94 civic hb.

The ls ran fine in my old car before I moved this motor over to my new car. We replaced the timing belt and water pump while we had the motor out of the car. After I finished the swap I started it up and it seemed to be running fine with just a little high idle. I adjusted the throttle cable and it seemed to be fine. I let it run for several minutes and didn't hear any weird sounds or see any leaking fluid, so I thought all was good.

I got the car out of the driveway and hit the gas to go down the street and realized that I have no power. I can't see what my rpms are because I haven't swapped over my other cluster yet. But it wasn't going anywhere fast. It seemed like something was almost holding the engine back. I had to get the RPMs up and nearly drop the clutch just to get it back up the driveway and into the garage. I never got a CEL so I don't think something is plugged in wrong. There were two of us that verified everything on the timing belt matched up and that it was on snug. I would think that if it were off a tooth or something it would misfire or idle erratic or something like that.

What could be causing an issue like this? Did I forget something when I hooked everything back up?

Thanks for any help.
-Ben
 
what ecu are you using ? wich harness are you using need more info ????

there are a bunch of things it could be
 
Stock p75 ecu, stock LS harness, stock dizzy, everything OBD1.

None of which were changed between removal from one car to the other.
 
i'd start with with the timing then seeing thats the only thing you messed with between cars

if the cams are off one tooth your going to have problems !!!
 
Ya but not total loss of power. It will just sound lumpy and be doggy. This sounds pretty extreme. Is the MAP sensor plugged in?
 
If the timing was off a tooth would it be a consistant idle that sounds normal? I would think it would be missing or idling erratic or something. I'll go check the MAF again and see if its not on all the way.
 
If the timing was off a tooth would it be a consistant idle that sounds normal? I would think it would be missing or idling erratic or something. I'll go check the MAF again and see if its not on all the way.

Yes, like I said it would sound lumpy. You'd be able to hear the misfiring and/or overlap that it created. I'm thinking bad or unplugged MAP, TPS, IACV...something fuel/air metering related. If your MAP was reading 0 bar, it would basically be chocking you out of fuel. The same if your TPS was reading closed throttle when it is very much open...
 
Well both MAP and TPS look fine. We didn't touch them during the swap though so I'm not sure what could have happened. How would I go about actually checking them to see if they are operating correctly?
 
Are you using a manual trans ls ecu?

Yep, and like I said everything is the exact same as it was in my other hatch which ran fine without a hitch. All we did was pull the motor, replaced timing belt and water pump and put the motor in the other hatch.

I'm still waiting on getting a timing light to check the timing, though I can't imagine that both my brother and I missed something putting on the new belt, we've done a bunch of TB replacements and never had a problem.
 
Put the stock engine harness back in. Why you used the integra one, I do not know. Both cars are obd1. The integra ecu will plug right in.
 
Put the stock engine harness back in. Why you used the integra one, I do not know. Both cars are obd1. The integra ecu will plug right in.

This is the same harness that has always been on the motor. You normally use the stock engine harness on this type of swap. There is no point to pull the whole harness off the old dx when the LS harness works just fine. If you were going to buy a swap from Hmotors it comes with the engine harness.
 
Well, obviously either your timing is incorrect, or there is a problem in the engine harness. Those are the two things you changed. The water pump won't affect your driveability. Check the engine harness and make sure you plugged everything back in correctly. If a sensor was bad you would get a cel.
 
Most likely you would get a CEL but you never know...Perhaps the fuel filter on this car is extremely clogged? Check the fuel pressure, check spark with an adjustable gauge to make sure you are getting the appropriate voltage. Man I hate diagnosing no start/no run/power loss online. Without having the car in front of you it's just a guessing game.
 
Also, you were sure that the cams AND the crank were lined up with their corresponding marks? The marks on the cam gears should be horizontal, on the inside, and pointing right at eachother - -, like that...
 
Yes, we made sure that all the lines matched up. We even used a camlock to lock the cams while we installed the new belt.
 
put a couple extra grounds on the motor and tranny to the frame and see what that does
 
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