Ecky

94 Del Sol VTEC, B18A1 (92-93, same cams as B1) converted to OBD1, B1 ECU (p72) and intake, for all intents and purposes it's a B18B1. Using B16A throttle body. FITV blocked off. Relatively new distributor (aftermarket), new 02 sensor (aftermarket), original MAP and TPS. No idle problems. New timing belt + water pump (~10k). Replaced plugs at the same time. New plug wires (~1k). As far as I know I'm on the stock fuel pump, and it whines. I got the motor from a guy's shed, came out of an automatic (less likely abused?) and supposedly had 67k miles about 40k ago. It has always smoked a little (black) when accelerating hard to around 7k, no changes recently. AFAIK the head has never been off. It probably needs seals.

What's wrong:

-Slight power loss recently as per butt dyno, intermittent but generally when car is warm. Car has always pulled a little harder when cold, but it's more pronounced lately.

-Gas mileage down *sometimes*. I have instrumentation for exact measurements and on the highway doing 65 I would typically get around 37MPG (B16 tranny ), recently it's been in the upper 20's intermittently. Sometimes it's fine, sometimes it isn't, and I can't seem to figure out what the variable is.

-Sometimes on a cold start I'll have a CEL. I could have sworn it was 7, but it's been about two weeks since I thought about it and I didn't write it down. I remember when I pulled the code, it was "No 1 Cylinder Position". I just Google'd code 7 and am reading now that 7 is "throttle angle" and N1CP is 9, so I'm not entirely sure which of the two codes it is. After the car warms up, turning it off and back on makes the light go away. I've seen the light 3 times in the past three weeks. Will get the proper code next time I see it.

It's not running poorly, gas mileage has just gone to **** and I think I've lost a little power.

As an aside, there's an odd rattling that varies with RPM. I just put my A/C back in so I think it's probably the pulley, but I'm a little paranoid. I haven't had a chance to track it down yet but plan to do so tomorrow, if I can. Thinking about doing a valve lash and visual inspection inside just in case. I checked the valves when I replaced the belt 10k ago and they were all perfectly within spec.

So, some Google-Fu reveals that if I'm getting a "No 1 Cylinder Position", I probably wouldn't be able to drive anywhere, so it's probably due to my aftermarket distributor. Would this be a problem, or can I ignore it? If the code is for the TPS, how can I test that? Does this sound like the TPS might be going? Where should I start?

bungalo101

What aftermarket distributor are you using? They are often the cause of lots of headaches.

There is no reason to not run OEM unless you are pushing high horsepower. Avoid the headaches and stick with OEM.

b16a swap

I had a bad tps sensor and it would buck and would not go over 4k probably something else

Ecky

I don't seem to have the email invoice anymore, but I got the dizzy on Rock Auto about a year ago and haven't had any troubles that might be attributed to it until this point. It looks like the stock one.

There's another bit of information that I forgot, that's almost certainly important: You know how when engine braking, our engines (all EFI engines?) have fuel shutoff? Once warmed up, I don't generally get fuel shutoff when I take my foot off the pedal, it keeps firing. It works fine when the engine has been running for a few minutes, but after 30 minutes of driving, forget it. I don't know exactly how the ECU decides to shut off fuel, but it seems likely that this points to the TPS?

tony_2018

You ecu isn't shutting off fuel unless your bouncing on the redline.

Ecky

Incorrect. Fuel shutoff happens when you let off the gas in gear, once the car is in closed-loop, and the RPM is above a certain threshold. In most Hondas it's around 1200RPM. It's generally referred to as "DFCO" or deceleration fuel cut off.

Source

You can verify this with something like an ELM327 dongle, Ultragauge/Scangauge or by testing the grounds on your injectors directly when driving if you don't believe me and Wikipedia.

Ecky

Tested the TPS, it was reading 0.63v with the butterfly valve closed, and 4.44 at WOT. I unbolted it and adjusted it until it read 0.49v at idle and 4.30v at WOT. Haven't seen the CEL yet.

JoeBlue

When is the last time you adjusted your valve lash? I have seen B's have issues with losing power if the valves are too tight or too loose.

Another possible is your wiring harness, sometimes intermittent CEL's are caused by flaky connections.

You should reset your ECU after you adjust your TPS too.

Ecky

Much appreciated, I'll clean the connectors, make sure everything is snug, and reset the ECU. I replaced the timing belt 10k ago and checked the valves at that point, all were in spec, but that doesn't mean they are now.

EDIT: Cleaned the connections, reset the ECU and checked the timing. Looks like because I timed it with the TPS reading wrong it was about 2° retarded. My butt dyno is showing an improvement, though I fear my rear mount might need replacing. My wife takes it to and from work every day, and when I took it around the block, I noticed an odd clunking that sounds to be coming from the rear mount when downshifting. Otherwise, it's purring.

Thanks for your help all! I'll check the lash tomorrow, and bump this thread if I have any further thoughts/questions.