Octanee

Hey guys, so I'm still having issues with this car. Rich codes both banks and fairly under powered, I do 0-60 in 9.5-10 secs, I feel sometimes it has decent power and other times it's not so good and it is noticeable. Car has 168k km

WHat I have done so far, valve adjustment, exhaust valves were tight with 0 clearance. Compression tested bank 2, 180, 185, 190 psi hot. Runs and idles smooth. Fuel pressure is good and within spec, test drove and fuel pressure was steady while code is being thrown, no pressure bleed off like a leaky injector either. I inspected timing belt markings, appears to not of jumped a tooth from what I can tell. Vacuum at idle is good, usually ~19-23 inches. No vacuum Leak found. Replaced spark plugs with 6 new iridiums. Blocked off egr but that didn't help, blocked off pcv, nothing, evap, nothing. Tested. Vacuum while revving up to see if vacuum dropped which is supposed to point to exhaust flow issue but it passed the test, hmm

Any suggestions on what to check next? Thanks!

I'm all out of ideas!

LoveMyTL-S

Anyone?

justnspace

iTrader: (1)

o2 sensors

nyckid

test/clean the maf sensor

Octanee

Thanks for replies, I have replaced 1 o2 sensor, I believe I mentioned that in the original post? It's an oem one from Honda. No change at all! I did it on bank 1, and it's still throwing the code.

The car has a map sensor no maf, I tested the one on the car and it read lower than all my vacuum gauges, so I replaced it and the new map sensor reads same as my vacuum gauges, it used to read about 3 inches less or 18 vacuum as to 21 at idle which would make it richer at idle.

But again that, hasnt fixed anything

losiglow

iTrader: (1)

Wow. Bizarre. If it's on both banks, I wouldn't suspect plugs, o2 sensor or injectors since it would have to coincidentally be the same issue on both banks.

What did you space your exhaust valves to? If the exhaust valves are open even a small amount during the compression stroke, some air/fuel mixture will seep by and possibly throw the codes.

You might try cleaning the throttle body for good measure. Also, try resetting the ECU (pulling the battery cable for about 5 minutes).

Do you have some sort of OBD II monitor? If so, take a look at your coolant temps to make sure your thermostat isn't stuck open.

Octanee

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It indeed is a very very bizarre issue. I'm an auto tech by trade and I'm scratching my head. If it was injectors they would go lean usually, or leak, if they leak id see it in a fuel pressure test, holds good pressure with key off. Plugs good, etc etc, and the valves I adjusted to spec, maybe give or take a thousand or 2., off the top of my head 12 thou? The exhaust valves when I pulled the covers off were tight, I couldn't fit a 2 thou feeler gauge under, I expected a good change after adjustment but it made no difference. Somebody said maybe burned or not sealing valves, maybe but you'd think upon a Compression test you'd see some loss, hot it had 180 psi and 190. I also put air in my comp tester and listened, didn't hear much going on, some escaped past rings but nothing terrible.

Octanee

just wanted to add, I removed the 3rd cat last night and tested it. no change at all, the 3rd cat also is fine and not plugged. so after a small drive with out the 3rd cat I re-installed it. I'm trying to think whats common to both banks. you'd think ok yeah map, fuel pressure, exhaust, but It's all been checked and checked. I'm banging my head against the wall!.

justnspace

iTrader: (1)

the primary cats are good?

Octanee

Thanks for the reply. They appear to be, I haven't had a look into the one on "bank 1" but bank 2 I did put my inspection scope down with removal of o2 sensor, I didn't see any issues, I didn't see any breakage of the catalyst structure in there or melting/discoloration. When I did the transmission I was also able to see the bottom of the cat on bank 2 and the bottom of it was good. So I'd feel good to say that bank 2 is at least good, again both banks are behaving the same.

Do you have a vacuum reading on your car at idle through the computer? Mine reads 21"

Octanee

Hi guys, I believe I have fixed it, this car has been the BANE OF MY EXISTENCE!. the only part I replaced on the car was the MAP sensor. I did have the factory one as well, I think The factory map sensor read higher by 1-2" vs a maybe accurate or inaccurate vacuum gauge. so tonight I put the factory one in, reset everything and instantly my short term fuel trims were ~0? +2%, they are normal! hmm.... , took it for a drive, LT fuel trims went good, bank 2 was on 0% still and bank 1 was -2%. short term on idle was always -24% like a crazy number, so it didn't take long even driving it for the LT fuel trims to set into the deep negative numbers, so after the same drive I would take before, I came in good.

now I believe for me what happened was some bad coincidence/chance and a not so accurate MAP sensor evidently I had bought. So First off I bought the car with the light on and the codes, I do all the checks I can think of, then read into it, seemed likely a map sensor, replaced that, no dice, so I then adjusted the valves, I think the idle vacuum did increase (been a while) but it must of, but again no dice, still throwing the codes, I replaced 1 O2 sensor and it never fixed it. so at this point I was exhausted, I did EVERYTHING and nothing added up. So Tonight I just thought you know what, I got the other sensor, lets re-check vacuum and read outs, and swapped the sensor, again the oem sensor read ~2 inches higher (or lower) but i mean 20 inches vs 22 inches of vacuum. So far from today shes looking good!

Car is running stronger for sure, I was 0-60mph in like 10.5 seconds, its now down to 8.5 but still short to that of most people around ~6.5 which I'd love to have! hmm.