I got a compression test done by Ty today on my 03 CL-S, I was throwing a P0172 (rich code) on and off, it would come every 3-400 miles and then turn off by itself. We changed out the plugs and checked coils and fuel lines. It runs a little smoother now, hopefully the CEL won't return, but he noticed my valves were pretty noisy, which I think reflects on my compression numbers.

190-195-200-205-195-190.

I think they are supposed to be around 220, he thinks that if I get a valve adjustment done, my numbers should go up a bit more. Any other ideas guys? And any SoCal people know a good place to get it done?

Thanks.

 

How many miles on the motor? Good part is the variance between cylinders is 15. Max variance is 28.

 

84k miles on the motor, god I hope it can handle the boost I want to feed it.

 

Hey Samir, that's good news. Hopefully that was all there was to it.
Did Ty say that he can do the SC installation for you?

 

He said once hes done with his restoration project, he can help me, but that won't be till 1st of next year, I think Accord v6 400m was willing to lend me a hand, so I think once I get my clutch in and valve adjustment done, Ill prob take it to him

 

Adjust the valves only if the noise bothers you. Your compression readings are fine, nothing to worry about, and adjusting the valves will not change them.

 

I read a couple threads on hondatech where after a valve adjustment was made, their compression numbers went up almost 20 psi, assuming my valves are out of spec.

 

If your valves are out of adjustment, it may effect your compression numbers. If the clearance is greater than spec, it has the effect of shortening cam duration. The cam will have to rotate more degress before taking up the increase in clearance which may effect cylinder filling, therefore compression numbers.

 

man i need to get a valve adjust. asap. i've got valve tick like a mofo now. its slowly getting worse but this just encouraged my lazy ass to get up and do it.

 

A few thousands of clearance will not effect compression readings.

 

bump.

I will be gettin my valve adjustment done on Friday, but my CEL just popped back on, same code I presume, P0172 (bank 1 rich code), I checked plugs, fuel lines, coils. Any other ideas of what to check?

I smell raw fuel at WOT, when the CEL is on, but now it stopped misfiring.

 

maybe something with your o2 sensor? report back after valve adjust. i'm supposed to get my valve adjust this weekend to

 

Yep Friday

At 80K I would replace my O2 sensor. Right now im at 77K and just haven't got around to it.

 

Yeah or I am thinking maybe my injectors are leaking, you think we'll have time to take a look at my injectors at the same time?

 

If the valve adjust doesn't do it, I guess I will just start replacing sensors, MAP, IACV, EGR, o2 and see if that solves it. Hopefully, I can figure it out before the blower goes on.

I dont think I even caught you name yet actually, Accord_V6_400M?

 

def. not the iacv. if that was dirty or broken your idle woulda been on crack. it also wouldnt give you rich codes, so you can eliminate that from the list

 

Yeah I am leaning more towards the MAP, because the code says it is either fuel pressure related or the MAP might be bad, but theres a completely different code for the MAP sensor when it goes bad, so who knows.

I think I might just run some Seafoam through the car first and see if I can just clean my injectors and all the gunk out, maybe that might just solve my issues.

 

That must be nice to have. Mine were:

235 225 215 210 160 150

Almost perfect, except for cylinder 5 and 6. With a leak down test, I'm losing 83% and 75% compression on those two cylinders. Losing 27% to 36% in cylinder 2, 3, and 4. Cylinder 1 was perfect with only losing 2% compression.

 

I read a few threads on hondatech, that seafoam in the oil and a fresh oil change also helps raise compression, so I guess I can try it out with the valve adjustment and retest my numbers to see if I get an increase.

That sucks to hear, Cocoa, did you find out why cylinders 5&6 are leaking? Do you think I should also run a leakdown test, my numbers are consistent, just a little low thats all.

 

The names Nick, as for seafoaming I love using that stuff we can do that too. Also your valves will start to sound like they need a valve adjustment if the oil is getting old and needs changing.

If anything we can just swap parts from my car to your when it comes down to stuff like the MAP sensor since all of my stuff is working properly.

I wouldn't worry as much about the IACV since your idle is probably normal and the EGR usually tosses its own code but its worth taking a look at, the O2 sensor is a really good preventive maintanence measure that will usually make your car a tad bit more efficient

As for the fuel injectors I guess I can d some simple voltmeter testing, not sure if that will be enough, dn't have too much experience testing them out but im sure I can give it a try. If anything you can try sending the old ones to RC for $24 an injector for cleaning or just get new ones like the S2K injectors later down the road since you wanted to boost the car anyway and im pretty damn sure those S2K injectors fit our fuel rails and even the lower injector base just right. I'll have to look through some of 02AV6's past threads and double check.

 

What does a compression test do and what problems can it help detect may be occurring with a car?

 

^its pretty much self explanatory. it checks your compression.

you stick a threaded attachment into where your spark plugs would go. theres a hose from the attchment to a psi gauge. when you crank the engine instead of it firing up, it will not fire up because you took out the spark plugs out. but in turn it will show you how much psi each cylinder reads.

it can tell you how much compression you have across the board and tell you in how good of shape your rings or cylinder walls are. i guess 100% compression on our engines is 240? correct me if i'm wrong. from there you can tell how much wear there is and if there is a compression leak.

in srehmat's case its telling him whether he can take boost or not

 

So how do you guys go about cranking over the motor while doing the compression test? It seems that it builds pressure the more you crank it so the question then becomes when do you know to stop?

 

it will only go up to a certain number and stay there. it doesnt keep building pressure because with every revolution of the engine, the valves let out the compression. it takes about 5 turns for the psi needle to jump to where you want it, then it stops jumping up and floats around 200 depending on the car.

 

Yeah, you just crank it enough times so that your numbers stay constant. It was fairly easy actually, for you guys who have never done it before. Just pull the plugs, start at cylinder #1 and work your way to cylinder #6, screw the tester in and just crank away everytime.

 

I guess either mines too cheap or I have super compression!! j/p

 

Keep us posted Samir.

 

i got my valves adjusted yesterday, and i feel so much better that my valves arent ticking anymore. but anyways the car feels much smoother and i guess the powerband feels more steady. i havent really drove it since so i cant really tell

 

Just got my valves adjusted, feels a bit more powerful and they arent ticking as loud anymore, and I put in some Corsport bushings and am getting a little smoother shifts. I think I will go for a seafoam and fresh oil change and retest my compression this week. I will keep you guys posted. Oh yeah as well as a UR crank pulley.

 

Im glad your happy, I still don't feel that its perfect so just hit me up next weekend when you have time and i'll see if I can redo it a little and some other stuff too.

 

Thanks, I will be back next weekend to get them tightened better.