CyborgGT : 1993 Accord EX wagon

[SSMAccord]

Hmmmm…how would the degree process influence your current situation? I think you did a pretty meticulous job when you did that process. Unblocking the EGR might actually help for your emissions test given what that system does with the exhaust gases.

If you need a set of blue top H22 cams, I have a set that I took out of a head over the winter. You can have them (free) as I don’t have a need for them and they might do you some good.

[CyborgGT]

Hmmmm…how would the degree process influence your current situation? I think you did a pretty meticulous job when you did that process. Unblocking the EGR might actually help for your emissions test given what that system does with the exhaust gases.

If you need a set of blue top H22 cams, I have a set that I took out of a head over the winter. You can have them (free) as I don't have a need for them and they might do you some good.

If I degreed them wrong, the intake/exhaust overlap could be off, which from what I'm reading could affect emissions, or worst case there could have been valve-to-valve contact without me realizing. In my searching, multiple other people were saying they had to put something like 3 or 4 degrees of advance on their exhaust cam (in a thread about Pro 2s in H22s), where mine only seemed to need 1 degree. But everyone's block and head surfaces are going to be machined slightly differently. I'll have to do a compression test to see if the cylinders are holding pressure, which should at least tell me if a valve is bent and not sealing properly.

The problem with me simply throwing EGR back on is my whole intake manifold and fuel arrangement (Euro R, RDX injectors, and a fuel rail designed specifically to get the two to work together). Because of the aftermarket fuel rail, the banjo fitting now hangs directly into the space that the EGR needs to occupy (see photo below; my block-off plate still has tape masking it off from when I was polishing the manifold). So I don't know how much I would have to change up just to get the EGR to physically fit again... and that's assuming the Euro R manifold can use a normal H22 EGR and doesn't require a unique one that's hard to get ahold of. Worst case, I'm tracking down a new stock manifold and different injectors to work with the stock fuel rail just so I can relocate that banjo. Although I did find these adapters that look like they allow the RDX injectors to fit to "all '90-'00+" Honda fuel rails: https://jackspaniaracing.shop/produc...f7849148&_ss=r




If it comes to me having to switch back to stock cams, even if it's just to pass emissions, I'll let you know. I really appreciate the offer.

[SSMAccord]

I forgot you have the Rosko fuel rail that puts the banjo there! The link you shared would allow you to run a normal fuel rail and the RDX injectors and restore the normal EGR location. In theory, all of this should work…I have been too busy/lazy to do a 2023 update but I am currently running the setup you described: Euro R manifold, stock fuel rail, RDX injectors and CNC adapters and CB7 EGR valve and a Hondata S300 and it seems to work as intended. I have a Rosko fuel rail but couldn’t get over the banjo bolt location so I didn’t end up using it.

The stock CB7 EGR bolts into that location on the Euro R manifold like stock and should work as intended as near as I can tell.

Yeah, degreeing the cams is unique to each set up. If your exhaust cam is at 1 degree what is the intake cam set to?

[Raf99]

Soo any car can have high CO / HC and fail, there's tons online. Same end result which is too much fuel or bad CAT, the easy things. A bad ECT sensor or O2 can cause issues as well but you would see all of this on the A/F gauge to my knowledge.
On WOT are you in the 12's or steady 14.7 across the board?

[CyborgGT]

SSM, my intake cam is at +0.5 degrees. No adjustments were made to either on the dyno. I'll talk to the tuner about that when I revisit.

Raf, at this point with the vacuum leak fixed, I'm thinking the rich tune that was mapped to fight it is causing most of the high CO/HC. But given my inexperience with all of this, it's that huge difference between my actual numbers and the accepted limit that makes me nervous about how much the tune can affect things. It makes me feel like either I made some other massive oversight, or these cams just can't pass emissions. All that said, at least I believe the vacuum leak is fixed, but I'm thinking of ditching the thermal manifold gasket just in case because I don't trust its ability to seal. Or maybe it would work properly sandwiched between two OEM gaskets? I'll have to see if testing the coolant temp sensors is possible, because I'd want OEM for reliability and those things are $80 a pop. I also read that a bad TPS can throw things off, so I'll make sure mine's calibrated right. I'll go through the engine again as much as I can think to without pulling it from the car for now, and then go back in for the re-tune to lean it out. Since the dyno, I haven't been full throttle with the car. On the drive to emissions, the only worrying thing I really noticed in regards to a/f was it getting super rich (low 10s) when decelerating to a stop.

[SSMAccord]

Interesting on the intake cam degree. Did you do a V2V measurement when you degreed the cams? To see if there is a sealing issue, you’ll have to do a leak down test to see if there is any damage. Also the cam sheet for the Pro 2s indicates that they are not emissions legal (whatever that means). Hmmmmmmm…need to do some thinking.

[CyborgGT]

Yeah, from what I was reading in one Honda-Tech thread, some people were saying there should be a greater difference between the two cam degrees... but again, everyone's engine is slightly different. My engine only has about 60k miles on it, so I'd imagine the head didn't need much machining. The block, on the other hand, was re-sleeved, and I wasn't told how much might have been taken off during that process.

I did not do V2V measurements, I'd have to look up how to do that if it comes to disassembly. I just stuck some play-dough on the pistons to check for contact there. But "not emissions legal" just means they didn't get them CARB approved like with the Tuner cams that leave the small lobes stock, it doesn't necessarily mean that they can't pass emissions. As far as checking for leaks, I was thinking a compression test will at least tell me if a problem exists if the pressure leaves the cylinders too quickly, and then from there I could do a leak-down to narrow down the source of the leak. I'd have to borrow a friend's air compressor for that one though. I do at least already have the gauges for both tests.

[Raf99]

I agree on the leak down test. but.... hold on. This is just a H22 running at 14.7. Everything is still sealed up (cams, valves, exhaust) just more aggressive for WOT response. This is no different than a normal prelude failing. Same engine, fuel, etc.
I like this post - https://community.cartalk.com/t/1991...and-co/33335/2

So you don't use an EGR but you do use a CAT? A bad EGR is the #1 cause of your symptoms (high CO / HC) on a normal car. Back in the day for Honda to meet regulations they came up with the EGR / CAT combo plus other items while keeping a 14.7 ratio. Assuming you obviously have the same ration (maybe not on WOT) you are going to fail IMO. You're going to have to implement some of the OEM smog features to meet standards. Not sure if a tripple CAT would help here too. Timing can cause rich conditions but not to the affect you are seeing on your readings...

(IMO / I'm no pro in emissions ...)

[CyborgGT]

From what I was reading about EGR, though, that system increases HC and CO a bit, if it affects them at all. EGR is only there to combat NOx, which my car is well under limits on (but that could change with a leaned-out tune). I did find this graph below... which, if taken in the sole context of air/fuel mix, does agree with that. It'll be interesting to see if, after some maintenance on my end (fixing that vacuum leak did make a noticeable improvement in idle quality on its own) and a re-tune to lean the mixture back out, if my HC and CO go down, but then NOx spikes. At that point I would definitely do the fuel rail conversion to get the EGR back on. And yes, I have a brand new California-rated cat, along with a brand new AEM wideband O2 sensor.


https://mechanics.stackexchange.com/...in-a-smog-test


An interesting post in the thread I found that graph in:

"Rich" and "lean" become too confusing because both can happen at the same time. When the injectors are dirty, they do not atomize fuel effectively. Micro-globs of gas pass through the combustion chambers unburned -- effectively creating a lean condition in the chambers -- so that the O2 sensors add more fuel to the mix, which in turn produces a rich mixture in the exhaust and uneven flame in the chambers. The cars EEC attempts to compensate by vacillating between more and less fuel every few seconds, which will also confuse the values on a scanner.

While I was fixing the vacuum leak and otherwise looking around my engine after that first test, I removed my intake pipe and noticed that with the throttle body open I could smell fuel in the intake manifold. I asked my tuner if he could test my injectors for a leak, but he said not to worry about it for now, that it should just be from his rich tune to get the car to idle with that vacuum leak we didn't know about. So apparently it's pretty rich. Wether it's rich enough to cause such a drastic failure in CO/HC, I guess I won't know until test #3. I'm obviously learning as I go here, but in a way I'm kinda glad my car did fail emissions, because I'm finding this information really interesting.

[SSMAccord]

Yeah, I think leaning this out will likely yield results that positively impact your HC/CO numbers. I wouldn’t discount the EGR helping either as it helps to burn fuel that vapors that weren’t combusted on the first pass through the engine. Where was your vacuum leak? At the intake manifold gasket?

I think you are likely ok on your V2V clearance, a bit on the tight side at less than .030 given the specs of the Pro2 cam specs, but likely still in a safe range.

[CyborgGT]

Vacuum leak was the brake booster hose being dried out and cracked on the inside, so a fairly significant piece to have fail. But with the tune left as-is, fixing it only dropped my CO by 20 points. I never noticed any unusual brake pressure issues with the car, though.

And yeah, these cams are pretty popular, so maybe I was too confident with them not giving me problems.

[Grumpys93]

Damn dude wish I could help on this matter. I fear emissions as I know I would fail in a heart beat. One thing that stuck out to me was you said you ran rich when you decelerated. Do you mean like engine breaking and coming to a stop? If so It should be the opposite and go lean not rich. I have no idea how emissions works, but if your smelling fuel coming out of your intake then that is pretty rich IMO and very well could be the culprit. How many tests are you allowed to have?

Curious on your Compression test. Have you pulled your plugs to see if they are wet or foul? Would putting in fresh plugs prior to the test help at all?

[UnicornHondaSE]

If the plugs are wet, putting in new ones probably won't help since he hasn't solved the wet issue.

Wet plugs sounds like too much fuel, which is due to the fat tune to compensate for the vac leak, IMO.

Or possibly a deficiency with your ignition system.

Leak down test is to check for damage in the head. Compression test is to check integrity of the rings. For the life of me I cannot at the moment remember how to perform a leak down test. Lol like how to hook it up, even though I have a nice Jegs or Russell tool here in the cabinet.

Sounds like he found the vacuum leak, or one of them. Cars as old as ours should have all vac lines replaced by now unless it's a low mileage garage queen and even then rubber doesn't last forever.

Love that throttle body, looks beefy for a na four cylinder.

[CyborgGT]

Yeah, I'll be trying to do both compression and leak down tests tomorrow. Getting out to the wagon, which is in storage 20 minutes away, is a bit of a pain to squeeze into my day. But suppose a valve is bent, therefore creating a condition where the combustion chamber is never completely sealed, wouldn't that mean that the bent valve would cause the cylinder to fail the compression test, just as much as bad piston rings?


I went to the junkyard last week...

Firstly, it was sad to see this 5th gen there. The color scheme isn't at all to my taste, but it was obvious someone put some real effort into this car, only for it to end up here:








Eventually I took home a small collection of random pieces:
- Manual gauge cluster, so I can swap out my auto fuel/coolant gauge face
- Spare coolant sensors/switches
- Front plate bracket (while I won't be running it in Colorado, it'll be smart to put on for road trips just to give cops one less reason to pull me over)
- The exhaust cut-out section of a coupe/sedan rear lip




Before I went out to the yard, I had a good look around the engine bay and had a long think on what I should grab. One of the things I found was these frayed wires going into the connector on the thermostat housing's temp sensor (and according to Majestic, it is a temp sensor and not a switch). One of the wires was hanging on by just a few strands, so hopefully this is is part of my problem. So you'll see in my new parts collection a clipped connector, which I soldered on:




The bumper lip section was needed because the one I had already plastic-welded on (after only eyeballing a good position for it) had to be cut back off during the exhaust fabrication:




I took the gauge cluster home to remove the one gauge face... only to once again get distracted fantasizing about a future custom gauge cluster using Speedhut dials. I wonder how doable this is on such a 'modern' vehicle, like if VTEC functionality is tied into the factory gauges and their circuitry being hooked up.




During the two drives out to emissions testing, both times the throttle seemed to be sticking by the time we got there (evidently it seems to have something to do with the engine warming up). We'd come to a stop, but the engine was still idling around 2,000 rpm. We found that we had to pull up on the gas pedal and the revs would finally drop. I'm hoping that this was the throttle cable and not the aftermarket throttle body, which are sometimes known to stick. For what it's worth, I have a cast Professional Products throttle body. It sounds like the billet throttles are the ones prone to sticking. Either way, I removed my throttle cable, and the cable action was a bit tough, but still worked smoothly enough. I could imagine it getting worse when heated, though, so I ordered a new one. Problem is, the new one was crap. You can see below that the threaded adjustment section was off, so I couldn't get rid of the slack. I took it back off, then exercised some brake cleaner and then silicone lubricant through the old cable sleeve and re-installed it. It's smoother now, so hopefully that holds up at least for a while until I can find a better-quality 'new' cable.




Something I didn't photograph was the wrapping of my ECU's USB cable with an interference-shielding sleeve, since my tuner said he was having trouble connecting to the ECU during tuning because of interference. I don't know for sure, but I have a feeling it might be all the gauge wiring going into the nearby glove box. I don't know how well the link below will work at taking you directly to the exact part, but at McMaster-Carr, the part number is 6971T11. Polyester fabric with copper wire shielding for its flexibility, of a 3/16" ID and overlap enclosure. We'll see if it works...

https://www.mcmaster.com/catalog/129/986/6971T11


I then gave the engine its first oil change since break-in. This is high-zinc Valvoline VR1 10w-30, combined with the assembly lube and graphite-looking stuff that the head machinist put on the cams during the engine build. It has seen idling up to operating temp a few times to check fluids, on-and-off trailers for trips to three shops, heat cycling at the tuner's shop while he messed with the tune at idle, the dyno session, and two 45ish minute round-trip drives to emissions. I replaced it with Castrol GTX conventional, because it was the only thing I saw at Walmart that wasn't synthetic or generically branded. This is all that was stuck to the magnetic drain plug:




I smeared it on some paper and didn't find much in the way of substantial metal shavings. It felt pretty smooth:




No real shimmer in the oil pan either. The stuff that pooled in the middle that I smeared around I felt was probably the graphite and an expected level of ultra-fine metal particles (I'm obviously no expert, but from watching YouTube videos on the subject). At least it wasn't rough between my fingers. The bigger specs are just bubbles; as I tried to get rid of them, more would appear:




After I poured that out, still nothing that worried me. Only a couple pieces of slight substance:




And the surface of the enclosed pan I poured it into, again its giving me confidence in a healthy break-in:




One mod I really want to do asap is an oil filter relocation. I knew it was going to spill onto the down pipe, so I wrapped it in some plastic to minimize cleanup:




I also changed my mind on reinstalling the EVAP canister for now. After looking at vacuum diagrams, it means re-installing the emissions "black box," which I can't find. Apparently I threw it away during the engine swap. A junkyard pickup would be easy, but there's a small vacuum line going from the charcoal canister to the black box, where it plugs into a "purge cut-off solenoid valve." I was hoping that would go straight from the charcoal canister to the intake manifold. I can't tell from pictures, but it looks like it'll mean messing with wiring. Not-so-long term, I do want to fully re-install all emissions equipment. One day Colorado will be as strict as California, and I want to be prepared for that. Given the re-wiring, I feel like it would be easier to do both EVAP and EGR at the same time. We'll see if I can pass emissions without them.

[CyborgGT]

Got some good leak down results, assuming I can trust this cheap gauge - and these are on a cold engine, I don't know how important that is for this kind of test. The air escaping seemed almost entirely coming up from the crankcase. No bubbles in the coolant reservoir, couldn't hear anything in the intake manifold (although admittedly I was doing this next to a busy highway), and putting my ear up to the muffler tips was like listening to a seashell with how faint the airflow was (a seashell might actually be louder).

I wanted to do a compression test as well, just to have those numbers, but the heat as it got closer to noon was giving me a headache. At this point I need to go back out there to make sure the TPS is calibrated correctly, but then I think I'm ready to ask the tuner for another dyno session. The throttle cable is still doing this weird thing where when I let off the pedal it still idles high (engine still cold), but then when I pull up on it from behind (I can't even feel through my shoe that I'm actually moving the pedal any), the idle immediately drops. Maybe my cable just has slightly too much tension? I can mess around with that, too.