Running rich, ignition issue?

[Tapi]

This may not be tune related at all but I'm helpless now with my swap car with LS1 engine.

It has 224/224 114 LSA cam and ported heads. Other than that it's stock.

It ran for few days ok. I noticed the idle was a bit shaky but not "lobey". A week ago a WOT run ended with trembling and MAF fail code. Unfortunately I didn't save the MAF code to a screenshot and I didn't have logging on when this happened. Clearing the code didn't help, it was still running poorly, especially near idle. No new code though. Now it's giving me P0172 and P0175 codes (System too rich, both banks). I guessed there was a faulty MAF sensor and I switched to a SD tune.
That didn't help. The next day car was running even more poorly. It doesn't idle at all and it must be kept running with throttle and it trembles a lot. Log shows -25% fuel trims and ALL spark plugs are black and soaked with gasoline.
I assumed I had poor plug wires or coils and I took one plug at a time out and tested it with that spesific coil. I have a good spark with all wires and all coils and plugs. Plugs are new.
I tested also fuel pressure which was low (42 psi) but if I had more fuel pressure, the problem could be worse.

I'm lost what to look into next.

[gtstorey]

What is the fuel system layout? Vacuum referenced?

[Tapi]

It's steady pressure, no vacuum reference.

One thing I forgot to mention: I haven't got rid of P0315 (crankshaft position system variation not learned). I have tried to teach it with scanner many times but rev's do not limit to certain level and the test won't pass. This code has been present all this time, also before this problem occurred.

[edcmat-l1]

Need to make sure the injectors are stock. Other than that the VE needs to be dialed in. It is numerically too high especially at part throttle, for that cam.

The P0315 doesn't make a difference about anything other than misfire detection. Turn the code off.

[Tapi]

Thanks. Injectors are stock and this combo worked few days fluently. I even passed emission sniffing test.
I noticed the VE numbers being high when I tuned this. I assume it's because it's still with car's original fuel pump and regulator (BMW 43 psi) and ideal would be 58 psi. I was about to replace the fuel pump and regulator this coming winter.

[gtstorey]

Did you adjust the injector data for the reduced pressure?

[Tapi]

No I didn't. But again: It ran fine for few days (250 miles) without touching the tune.

[blindsquirrel]

An ignition problem (misfire) will cause the O2s to read lean, not rich. O2s measure oxygen not unburned fuel.

[Tapi]

Could one or few faulty injectors cause this? This engine was bought as a whole but I could see it had sit a long while. I tore it down, replaced bearings, piston rings and such. Injectors are original.

On the other hand if an injector would leak a lot, then other cylinders would look lean. Now they all are wet.

[blindsquirrel]

Not likely to be a mechanical problem with an injector, since there would have to be an equal number of bad injectors on each bank with the exact same degree of problem, or else you'd get a big obvious imbalance between banks.

[blindsquirrel]

I think I would be checking physical ignition timing (piston stop, fab up a timing pointer and mark true TDC on the balancer). Compare measured timing with a timing light to what the PCM says it is. The problem you'd be looking to prove out would be a reluctor wheel on the crankshaft that's moving and causing the timing to get progressively more retarded.

[Tapi]

That sounds like worth to check. Thanks.

[abc]

Did you check the valve train?

Have you tried to work on the VE table to bring the fuel trims in check?

[Tapi]

Havent checked under the valve covers yet. It doesn't sound odd but I'll check that too.
I haven't touched the VE after I got it dialed in before activating MAF and dialing that in too.

One thing I could try too is move the ignition with scanner when it's running and find if there is a spot where it's running better. The same goes with adjusting AFR manually with scanner.

[Alvin]

This to me looks like it just needs to be tuned more. I don't see anything out of the ordinary with the trims other than the VE tuning must be off. Both banks agree with each other.

If you had a code regarding one bank.. its likely that one was just a bit more over the limit while the other one wasn't yet high enough to set the code.

The only way going from a MAF tune to a SD tune would be better is if the VE was actually tuned in. There are lots of half tuned stock VE cars out there running somewhat normal.

[Tapi]

I attach here the log which was taken few days before this problem started. When the problem occurred, I switched to SD mode but didn't touch the VE table.
So the car worked few days with the tune I have. This started at once in one WOT run and became worse every time I started the car.

The log "4.11. manual tuning.hpl" is taken today when I disconnected breather hoses (to check if there is gas in oil which is messes the AFR) and I test different ignition advances to see if it runs better in late or advanced ignition.
It sputtered all the time and I had to stop since my eyes hurt because of the horrible fumes of unburnt fuel from exhaust.

I also tested with 25% off from VE table if it would run but it didn't change anything.

I will of course check the timing which blindsquirrel suggested when I get other car off from my lift.

[Tapi]

This seems to be solved now. Almost all valve springs were broken. I havent disassembled the heads yet but I hope valves and guides are OK.

This has TSP 224 cam with .600" lift. Valve springs I bought from Ebay falsely thinking I was buying TSP stuff but the ad didn't actually say them to be TSP parts, only the heading mentioned Texas Speed and the package was delivered from China. These springs were supposed to be for 0.660" lift and they came with retainers and seals. When installing those I wondered that they don't look polished, they look chromed. Now I know those were chromed and I should have thrown them to the bin before destroying the engine with them.

Any suggestions for new springs? Beehive seems to be out of options with .600" lift?

[2xLS1]

That Serius guy will be along shortly to tell you there is nothing wrong with Chinese parts.

[SiriusC1024]

Why are you lisping at me again?

[abc]

Are you removing the heads or doing the work with them on the engine? If leaving them on the engine you need to do a leak down test on each cylinder to find out if you bent any valves. There is also the chance you have compromised the lifters.

Floating the lifters at high rpm can reek havoc on the roller end of the lifter. Check all the push rods for bends also.

Do you have your cam card? If so any good cam supplier can get you the springs you need. If no card, contact TSP and find out what springs they sell with that cam.
Ideally you would want to check installed height and set the proper seat psi of the springs.