73 replies to this topic

[brivinci]

Very good. I wasnt thinking in terms of a full cycle. I was really just looking at how fast it switches. That makes a lot sense after reading that. I think I am going to give a new sensor a try. If it turns out to not be it, oh well. I like new, shiny things any how. haha

 

I'll keep you all posted.

[xrocketengineer]

I would still try with the sensor disconnected. But also disconnect the battery for a minute or so before restarting the engine.

[brivinci]

Will do. Do you know if unplugging the lambda will cause any odds to come up? Wondering if I will need the scanner for this.

[xrocketengineer]

You will need the scanner to see any codes since there is no "check engine" light. I got  another data point for you. I just came back from helping a friend with 2001 Mustang V6 with 230,000 miles. A few weeks ago the car overheated and had to be recovered. The tow truck driver said that the head gasket was gone because the engine was running very rough and it had what sounded like an exhaust leak by the engine. Anyway, my friend had already replaced the radiator since it had a crack and refilled the cooling system, new plugs, HT wires and coil. The car was still running badly, but there was no water in the oil and no oil in the water. He could not make heads or tails of the diagnostics since a bunch of codes were showing up. I had suggested to him to disconnect the primary oxygen sensors but he had not done it yet. Today, when I got there he pointed at the right tubular exhaust manifold saying that he thought it was cracked creating the noise. And sure enough it was cracked right at a weld. He had already disconnected the sensors and car was started and ran perfectly. The left side sensors were reconnected and we went for a test drive and it ran great, my friend said that he had not been able to drive it until then. Very smooth idle, It did not overheat and  it burned rubber in first and second gears! A new right manifold has been ordered since the air leak was definitely screwing up the right upstream oxygen sensor. Other things might still need attention but until that is fixed there is no point on messing with anything else. My friend said that now he felt 99% sure that the heads were fine. So much for tow truck diagnostics.   

Edited by xrocketengineer, 12 August 2013 - 08:52 PM.

[brivinci]

Well, I ran the car till warm and then turned it off an disconnected the lamda. I didn't drive the car as it felt fine before. Easy to tell there's a problem in the shop. Anyway, disconnected it and the car ran exactly the same. Smelly, with small puff under throttle stabs and if you peg it from idle, it hesitates/stumbles/intake backfire (on occasion) just like it had with the sensor connected. Guess what I am ordering tomorrow? Haha.

Now, here is something I was thinking about. Oil consumption! My car is eating the stuff for breakfast, lunch and dinner. About a quart every 500 miles. I wrote about it in a different post. Worried I am going to buy a new lamda and then very quickly ruin it with all that oil possible going out the exhaust.

My plugs seems to be burning well enough. Not perfect but nothing to say crazy oil in the cylinders. Thinking maybe my valve guides or seals. Still, wouldn't I see the plugs really sooty? When I pull the lamda, I guess I will see how bad it looks and most

[brivinci]

Scratch that a bit. I rechecked the plugs tonight and will post pix in the AM. There is actual carbon build up on the treads and top surface of the plugs and cylinder 2 is worse the the others. Actual build up on the electrode (or whatever you call it. It's late). Really think I have a problem in my head. Maybe it is what caused my lambda to go bad? Rechecked the lambda and it really is slow to switch.

[IainStallard]

How many miles has the car done?

[brivinci]

The car has done 46k total. This latest motor has done about 2000 miles. Those plugs were new on rebuild. I have not noticed this much build up over those miles until now. I can say that my valve train is very loud. Sounds like a diesel I think. The head has been skimmed once and the valves re-lapped in with Swiftune dual springs installed. Not sure I remember checking the valve guilds. I mean, I am losing a good amount of oil somewhere. The plugs show buildup on the threaded area and lots on cylinder 2. I am also getting smoke and my exhaust smells like its burning oil. Could this be it?

 

Tried posting pix but it wouldnt let me from Shutterfly...weird??

Edited by brivinci, 14 August 2013 - 03:42 PM.

[Fast Ivan]

Have you done a compression test yet? Also have you checked the tappet clearances?
I think you need to pull the head anyways, the oil consumption is your main issue here, not the lambda, that comes later I recon.
The oils getting burnt if you don't have a leak, its either coming from the top (head) or bottom (piston/bores) hopefully its head related.

[brivinci]

I did do a compression test. It showed right around 200psi across all 4 cylinders. That was on a warm engine, all plugs removed, and throttle open.

 

I feel it is head related. My valve train is super noise too. Something it going on up there. I have checked and rechecked my valves. I will do it again, just to be sure, but they have been done at least 4 times in the last 3000 miles.

 

That #2 plug really tells be it is head related. You know that one color printed page in the back of your Haynes manual that shows the different plugs and their related problems. Mine looks like the one for worn valve guides:-)

[brivinci]

This is been awhile but I believe this problem is a two-part issue. First issue being very worn valve guides. I think that is where my noisy valve-train is coming from. That is dumping oil into the cylinders. So much oil that it has ruined the Lambda sensor. Maybe not but the Lambda is not operating as it used. Maybe it went bad on its own but I think the super oily exhaust didnt help. Sooooo, the Lambda is now bad and that is overfueling the car and making it spit and backfire.

 

Either way, I have ordered a new head from Calver. Wanted a new, upgraded head anyway. That with a new Lambda and I am hoping I will be back in business. I will keep you posted. Always good to post a problem solved, right?

[Fast Ivan]

Yep always good to post the solution.
You won't go wrong with a calver head.

[brivinci]

I wanted to repost a conclusion to these issues. I FINALLY bought and installed a head over the weekend. Keith Calver really helped me out and was a treat to work with. Being in the US isnt always easy when it comes to these cars but he was great. The head finally arrived and I spent the better part of Saturday (much to the annoyance of my wife who wanted to do work around the house) trying to get a massively stuck lambda sensor out. Oh, it did finally come out, minus the damn threads. Spent the rest of that day running around, trying to find a metric M18 x 1.5 tap. All that sorted, I got it back together at 4:30am. Worth it though. Above I was really just writing my theory on what I felt was the issue. It was great to be proven 100% correct. The valve guides were worn to hell and the lambda was ruined. With all installed and running, the car is completely transformed. I know it will take a little bit for the exhaust to be "cleaned" out from all the nastiness that has been pouring out my motor but it is not spitting, no more backfires, is not smoking or sooty. FINALLY!!!

 

On a side note, the head is just wonderful!! It really makes the SPi much more usable on the streets. Pulls so clean, all the way through the rev range. VERY happy with Keith's work and he is so helpful

[xrocketengineer]

Great to know that you got it resolved and that your repair plan worked great.