c0ntra

Hi,

I've been struggling with an annoying issue with my 1993 Civic CX automatic for some time now since I picked it up as a daily driver 2 years ago. The problem is essentially that the car struggles or feels flat at anything more than part throttle, but runs fine at WOT. If I keep my foot light on the throttle, the car boots around alright. If I press a little harder on the throttle however, the car sounds loud and hollow underneath the shifter area (no backfiring though) and doesn't increase in rpms, like its running lean. If I press any harder, the engine kicks down a gear and takes off, making my drive sometimes a bit unpredictable.

*The car doesn't throw any codes, and the check engine light bulb is good.*

One oddity I should mention about my car is that the engine block says D13B. I'm not sure if all CX's say that or not. I was under the impression the engine was supposed to be a D15B8

What i've replaced on this car already this month:

- New distributor
- New cap and rotor
- New plugs (copper). When inspected, they're clean and white
- New wires
- New fuel filter (helped with my off the line smoothness actually)
- New catalytic converter (car passes smog no problems)
- New PCV valve
- New thermostat and rad cap
- New battery
- TPS sensor reads 0.55v to 4.75v when tested
- Re-soldered my main relay
- Re-tightened all the spades on the ICM and Coil inside the distributor
- Timing belt isn't off a tooth (I just checked it again today to be sure)
- Timing light says everything is ok
- Installing a new fuel pump today (I stupidly busted off the return line spout removing it for inspection last night)

All of the grounds are tight as far as I can tell. I'm starting to lean towards the problem being with my map sensor, or fuel pressure regulator, but I'm honestly not sure.

The only other thing I should mention is that I believe the auto trans is a little overfilled. I plan to drain it this weekend and refill it myself.

Any advice would be appreciated.

thanks!

BrandonR

Two things. One, the D15B8 has very little power to begin with, couple that to an auto tranny, then you get essentaly the weakest link. It's not going to seem fast or smooth because of the power it lacks. Second, If the block says D13B, then it IS a D13B and has been swapped. (Weird thing is, the D13 and D14's never made it to the states) That makes it even worse, because now you have a 1.3L engine trying to accomplish everything. Where are you located?
My advice to you is to stop throwing your hard earned cash at it and leave it alone. Either swap the engine back out for a D15B8 or even a D15B7. Later, BR

c0ntra

I'm located in canada, but we get a lot of imported jdm engines here, so who knows what the former owner did in terms of swaps. It would appear the head is a D15 head for sure, so I cant explain why the D13B block. As for the lack of power, I have to disagree a little. I'm still new to hondas, but my last one was a 1991 Civic wagon and even with its dual point injection, it had WAY more pep than this car.

There's definitely something wrong, the CX shouldn't have to shift to 2nd or 1st at 4500+rpms just to get up a gradual hill.

BrandonR

A D13B would, and also your dual point wagon had 93 Hp versus 70 Hp.

94EG8

Car should actually have a D15B7, we didn't get D15B8s in Canada. Which would be putting out 102hp. the D13B only makes 75hp, and really doesn't have enough power to pull a car that heavy with an automatic. Theres not really anything you can do about it other than swap it.

Sr420Det

i cant read

c0ntra

Thanks for the input everyone, but ''Its a D13B'' doesn't answer why it wasn't driving like stock at all. Even several shops said it wasn't normal to bog so much.

If it helps anyone, it turned out that a combination of replacing the fuel pump, draining and refilling my tranny to the proper level, as well as readjusting the kickdown cable helped solve my problem. I can now go uphill doing 60km/h without slowing down part way up lol. (I'm assuming it was always in the wrong gear as well as maybe low fuel pressure)

On a side note, I still think this car has more than 75hp though, especially with the pm3-7 head its got on it which I'm reading now might be from a D16. Strange combo...

Jmfsampson

Did you ever figure the problem out. I recently bought a 92 eg hatch and the d15b8 was doing very similar things. It would bog even when it wasn't under a hard load. I understand the hp is weak, but I still feel that it should have a reason for this problem.

crayzd

Check the timing, especially if you have replaced or tweaked the distributor. If it's off even a little bit it can bog down the car a lot. I just went through this a few weeks ago after replacing mine.

bcumbie

Was it running this way when you bought it? The previous owner could of changed the timing belt and got it off a tooth. I would check that too.

bcumbie

It could've jumped a tooth too.