Rep Power: 0

Hey all, to start I have a 98’ civic EX with the d16y8, bought it with auto to manny swap (S40). I’ve always owned shitboxes and worked on vehicles out of necessity, NEVER been to a mechanic besides tires and inspections. Used to work as a tech now I work maintenance at a foundry, by no means a mechanic. Recently rebuilt a 1980 Honda cx500 motor successfully, stripped bike to the frame just for some background. I’m not afraid to do work and want to learn just lack experience and lack anyone to teach me. My lowest skill set is electrical work. I bought this as my first project, since I’ve bought it I’ve overhauled the entire suspension, all truhart and moog parts, replaced my dizzy and spark plugs about 2 weeks after buying it, refreshed interior and that’s about it. Anyways…

as stated I have a crank no start condition at the moment. First issues started with the engine stumbling/backfiring/loss of power above 3-4k rpm’s. Around this time then the car wouldn’t start when I was parked on a hill facing up, subsequently started after moving the vehicle to face down the hill (1/8 full tank). The pump was audibly whining louder as well, figured it was going bad. Car ended up dying on me a day later (a lot of stumbling, eventually just quit on me, going about 50 in 4th gear on a backroad, had just come off the highway after 15-20 miles, started to stumble on me towards the end of this) and towed it home. At this time pump would not prime, but would hear the relay click after 2 seconds. 2 days later I replaced the pump, sock and filter. Started up fine after. Let it idle for about 5 minutes, then drove off fine. After about 10 minutes I was going up a roughly 1 mile long hill w 25%ish grade and the stumbling/backfiring same as before started again. By the time I turned left at the top of the hill it died on me. The only correlation I’ve found is it won’t stumble until I hit 3-4k rpm’s, and lowkey felt like it wouldn’t do this until 3rd or 4th gear but can’t confirm this. Both times got the car up to highway speeds, 60-90mph. Towed home.

I’m lazy and don’t know proper diag work and read about the main relay and ignition switch issues on these cars, I checked my main relay and visually appeared okay. I resoutered every connection and tested in the with no luck. Idk how to bench check these, But got a new main relay (spares never hurt to have anyways) also no luck. I went to replace the ignition switch but my replacement only had two plugs, the one on the car has the same two but also has some wires tied into the one plug going to the ignition lock cylinder. I wasn’t sure if I got the wrong replacement or if extra work was needed so I left the original one in the car. I’m not ruling this out yet, just wasn’t sure what to do.

I randomly decided to check spark, even though my symptoms til now I thought seemed fuel related. No spark. I didn’t check my dizzy because I don’t know how and it only has maybe 8k miles on it. Not ruling this out but very doubtful that this is the issue. Spark plugs were replaced at the same time, but not plug wires. But they appear to be in good shape, visually inspected them and they seem pretty new. Checked the timing belt by looking in the oil cap while cranking, good here as well.

there’s more to this as well. I currently have 7 CEL. 4 being A/T codes related to the manual swap from when I bought it. 2 being 02 sensors, bought it catless, recently welded in a new cat but no sensors. The last one is a knock sensor code. After reading online and looking at my car I have no knock sensor and visually couldn’t even find the electric plug for it. They’re no sensor and they installed a plug in the sensors place. If I’m correct Someone also would’ve had to bypass this and the 02 sensors for vtec to still engage which it definitely does engage.
recently found as well the intake on the car has no machining done to it for an IACV. Idk why maybe just cheap eBay part? Car idles fine most of the time, sometimes purges between 700-1300 rpm’s, but settled down after idling a few minutes. I just got an intake from the junkyard and an IACV and intent on swapping them eventually. Not sure if any of this is related to my issues, all of this has been like this since I bought it and until now car has always ran really well. No smoke from exhaust, exhaust smells like a healthy Honda (have had people tell me this as well), the two oil changes I’ve done since purchase (8-9k miles total) have both seemed healthy as well. Power delivery has always been good, car is super fun to drive and handles great, still gets like 25-30mpgs too with my heavy foot (can only be so heavy in a stock single cam lol). I’m almost definitive my pump did go bad. The fuel filter wasn’t that dirty though but still replaced.

I’m just lost on what to look for now. I’m not sure if it could be an electrical issue relating to the bypass for the vetch solenoid relating to the 02 and knock sensors? And if it is, why now?
could the issue be the cam position sensor? I’m not super knowledgeable with this stuff I’m not sure if that would cause no spark, and if that is the issue why would it run fine after sitting two days and die again in the same manner? To me it seems like something is losing connection or signal but I haven’t been able to make a correlation with the symptoms. The intermittentness of it running kinda crappy, dying, starting up fine and then dying shortly after has me pretty lost. I live in pa weather has been all over the place the last week or two, from 85 during the day to 40 at night snd a lot of rain. It’s starting to get overwhelming and doesn’t help that I don’t have anyone to ask for help. I have tools, a multimeter (that I barely know how to use) and if I need to buy tools to figure this out I will, I ain’t broke anymore lol. I think until I hear any responses I’m going to look up how to check my dizzy/ignition coil, and try to go from there. Any help would be greatly appreciated.

thanks,
-Gavin

 
Rep Power: 222

These cars dont like aftermarket electronics. Go get a distributor from a junkyard. Throw a new oe coil and igniter in the junkyard dizzy if you want but you shouldn't need to in order to get the car running. What are the o2 sensor codes? Replace only with denso or ntk.

 
Rep Power: 0

So got around to looking at the car tonight. I checked for spark w the cap off from the ignition coil and had spark, checked with a test light on positive battery terminal to the igniter, and the negative on ignition coil. Power and good signal while cranking. Also checked the signal wire on the injectors, pulsed while cranking as well. Then the car starts when I put it back together, idles for a while then dies. Without taking the key out of the on position I check spark again, didn’t signal to the igniter, then it out of somewhere picked back up signal. Probably when I poked it. Assuming the igniter is bad, there was a slight amount of oil inside the cap so I ordered a OEM dizzy. Let it idle for almost 25 minutes, jiggled around and made vibration/slight tugging on the wires and components of the ignition switch, main relay, tapped on the cap, jiggled spark plug wires, basically everything that would cut signal to dizzy. test drive went find first few minutes, thought I felt one hiccup and went to turn around as soon as I put it in neutral it died on me. Crank, crank again, 3rd crank starts. Not more stumbling besides high rpm’s on the way back. Died going down the hill to my driveway and twice going up it but got it home. Going to wait for the new dizzy and go from there. Thinking the igniter is losing connection internally? Will post follow up

 
Rep Power: 222

Could be, i just know aftermarket dizzys are a complete crap shoot with these cars, might work for a little bit and then die, or it might give you issues from the start

 
Rep Power: 0

Sorry it’s been a few days but got the car running. While testing the igniter it would go to ground w the test light when I would touch metal inside the dizzy housing under the cap, then have spark. Replaced dizzy with an SKP dizzy, been driving 3 days now no issues. Only thing is now between the pump, sock and filter, and dizzy, now car has a from what I feel is a loss of power. I’m not sure if Vtec engages I have to test it but it feels like across all rpm’s a slight loss of power. I kinda thought this was happening before it died on me (issue from first thread) but I had a bad cat that was clogged and replaced w a 150$ aftermarket one. Car doesn’t have upstream or downstream 02 sensors or a knock sensor all bypassed. Like I used to be able to cruise on the highway around 70-90 3500-4500rpms and be able to accelerate a decent bit and never leave 5th but now I almost have to floor it to maintain speed. I bought new plugs gonna check the old ones (not that old replaced when I bought last October) and replace them got NGK platinums and maybe test fuel pressure, then check if the vtec solenoid is engaging?

 
Rep Power: 222

Check timing, lack of primary o2 could be part of it.

 
Rep Power: 0

Thanks for the replies Colin, I’ll do that next time I have a chance. Thinking possibly it could’ve skipped a tooth or two? Now in the case I want to add the 02 sensors and knock sensor, my question is why they would’ve been deleted in the first place and how they bypassed them to for vtec to still engage, is that something that is changed with the ECU? I’m hoping they left the plugs for them but I doubt it, everything on this car that I’ve done from audio to suspension has been an absolute hack.

 
Rep Power: 222

Someone did some hacking. Is that the engine that's supposed to be there?
might have skipped a tooth, wouldn't hurt to check