A few different problems, and I'm not familiar with CRXes or OBD0!

1988 CRX HF, original D15, mechanically stock, 164k miles or so.

Problem 1

When I got the car I began to notice a slight hesitation in acceleration, so we replaced the stock TPS with a Blox TPS. Everything seemed fine. (Might be worth noting that before the TPS was swapped, we Seafoamed the car and the CEL came on for the VSS even though it's always worked flawlessly.)

Just in the past week though, which is a week or two after the TPS was swapped in, the car has began to somewhat violently buck on acceleration under 40 mph. It's usually just one or two bucks and then it's done and continues on fine.

The day after this began, when I started the car after having let it sit the CEL came on (7 and 17). I didn't clear them, but after a short drive totally maybe a mile and a half, once I turned the car back on the CEL was gone.

The next day it seemed to run better. It was warmer and drier out. I sort of think it bucks more when it's cool out, but that could be chance.

I'm thinking perhaps I need to go out and make sure the TPS is set right.

Very appreciative of any help!

EDIT: 11-09-2011
Tested C7, C12 and C13 from the ECU to TPS. No breaks. Swapped out the ECU.

Still having the same code thrown.

EDIT: 05-08-2012
Replaced speedo head some time ago and have not experienced the problem again. If the cable begins to come unplugged from the transmission the needle will start to shake btw.

Will not be revisiting "TPS" issue because the engine has been swapped. Issue has not reappeared with the D16Y8 currently in the car (which I know the history of that engine back to 76k).

 

Any suggestions for any of the above listed issues?

 

7 and17. Vss and tps. Check voltage ofbthe tps. See if it falls within spec.
Those symptoms are synonymous of a failing/out of range tps.
Does the speedo work? Did it ever not work? Have you cleared the codes since sea foaming yet?

 

I cleared the codes since the Seafoam, but after the TPS was recently replaces the CEL came on and both codes were there again.

 

And the vss has always worked fine?
You'll have to check tps voltage. Recalibrate it if necessary

 

Speedo has always worked just fine.

I'll check the TPS here soon. Friend who installed it said he set it a few weeks ago when he put it on.

 

Agh yes. As you stated in your first post. Speedo always worked flawlessy. Sorry.
I'll have to look up a diagram to see how the PCM sees signal.because the PCM is thinking that it's not working when it is (obv). Lemme get back to you on that

 

Thanks for all the help so far!

 

#3. If the alternator nuts or the through bolt can't be removed with hand tools, and you can't get an impact in there, you are going to have to A. Take it to a shop to remove (you can drive it w/o the alternator to change the brushes at home), or B. Hoist the engine to get better access.

I fought and fought with my alternator bracket on my VX engine *while it was out of the car* and I still had to get creative to remove it. Failing that creativity, I would have required an impact hammer to loosen things up. There would have been absolutely no way to do it while the engine was still in the car. I am presuming that the alt mounting location is very similar on a 4G as it is on a 5G Civic.

 

As far as I know the alternator location is roughly the same on all '88-'00 D-series engines. At least the ones I've seen are all on the left rear lower section of the engine.

Figured I'd have to bring it to a shop. Oh well.

Had plans today so haven't been out to mess with the car. Also not feeling so great.

 

^ I'm actually curious what trick they would use to get it out. Try to find out!

PS. I'm am feeling a similar pain with my whole rear suspension - my impact of 350 ft-lbs is not powerful enough to loosen ANY bolt in the rear. I will be taking it to a shop for them to loosen everything back there and then re-attach with anti-seize before I can work on my suspension.

 

Heat, when applied correctly, is by far the best tool anyone can have.
Oxy/acetylene torches are the only way to go for seized suspension bolts.

For the alternator, if the bolt/nut is stripped, they may need to get creative with a grinder or cut off wheel. Maybe even the torch

 

Checked the TPS. It's almost right dead on (.5v and 4.46v iirc).

Distributor began making a horrible rock tumbler, grinding sound when I parked the car today though.

Opened it up and found lots of dust and some small pieces of debris and broken bits, but couldn't find out what exactly was broken.

So it looks like I need a new distributor.

 

Oh, CELs popped on today again btw. I cleared them before I even left the neighborhood, but they popped right back on. Turned the car off, ran an errand and the CEL stayed off the rest of the day but the car started bucking again (doesn't normally have a problem if the CEL is on, it seems).

Battery light still comes on whenever. Brushes still sitting in my glovebox, waiting to go in...

 

for the alternator its a slow process but you can get a wrench in there and take the alternator mounting bracket just off the block. if its like my crx dx one bolt up top and two at the bottom.

i would double check all your grounds and check and make sure your speedo cable didnt come loose somehow happened to me just make sure its fully sat in the tranny

 

oh and also i have a service manual for the hf and si and just checked the wiring for the VSS sensor and it just has a ground and i believe its a yellow wire that runs to pin B16 on the ecu thats all! you can spin the sensor from the back and it should create continuity 4 times between a and b terminals per revolution! hope this helps

 

The problem isn't reaching the bolts. One of the nuts is internally stripped. It just plain won't come off and the impact we have here won't fit.

My speedometer works absolutely flawlessly. Not sure why I have the code, but I know Hondas with distributor problems can get some weird electrical gremlins, so I'm thinking perhaps it's my obvious distributor problem which reared it's head today. My only problem with the VSS/speedo is that I have a code for the VSS. There is no mechanical problem.
I can try to check this, I suppose, if the code ever pops on again, but I have to focus on finding a new distributor first.

 

Car is still having problems three months later.

Seems to mostly happen under 40mph and probably not a coincidence that it bucks when you just touch the accelerator or just let off the accelerator.

I just got a manual today finally.

Looks like from this point it's probably narrowed to either a bad ECU or a break or short in RED/BLU wire between the ECY (C7) and throttle angle sensor. (Page 11-57, 1988 CRX Service Manual)

 

Cel 17 came up for a while on the my ef it turned out my battery ground was a little loose tightened it up and it hasn't came on since

 

Tbh I'm not worried about CEL 17 at all.

I worried about CEL 7/TPS and the way my car has been driving. It's nearly not drivable in this condition.

 

CEL popped on again today. CEL 7 only.

As long as the CEL was on the car drove great! But when I turned the car off the CEL cleared itself.

 

Tested the wiring from the TPS to ECU (black small plug on the bottom, which goes to the round white connector on the passenger strut tower and then to the TPS, btw).

Wiring is good. Leaning toward an issue with the ECU now.

 

when the ecm registers code 7 it goes into limp mode and is ignoring the TPS it sounds like.

the TPS needs to be scoped with a DVOM and the wiring checked to start.

edit: just read your last post.
still, have you scoped the new TPS since it started throwing code 7?
know anybody with an ECM you can swap out?

 

If you mean checked the TPS with a mutlmeter, yes, we did that. It read perfectly. Everything works awesome while it's idling.

When my CEL came on the other day I'd actually had the car sitting in the driveway idling for quite some time. The car warmed up all the way and then I went on a drive. As soon as I began backing up out of the driveway the CEL popped on. It usually seems to pop on down the road, which is probably when the car warms up.

So we've checked the CEL, changed the TPS, checked the TPS with a multimeter, and checked TPS wiring (C7 to TPS/ECU).

Looks like the manual also says I can test the GRN/WHT wire between the ECU (C12) and TPS and the YEL/WHT wire between the ECU (C13) and TPS.

I can't find anyone with an HF ECU locally. I was ignored in the local thread.

 

I don't have an HF ecm either,
in the meantime, you could try scoping the TPS @ the ecm as well and also do a wiggle test on the harness while you take your readings.
Also, I have to ask:
You do sweep the throttle slooowly and look for voltage jumping around right? not just the min/max.