Will car idle with plenum off, so once I change the regulator do I need to reinstall everything or should I just fire it up.
Although i have never tried it, it should run. You will have to plug the 8 vac lines that go to the base of the ITB's . It should idle with the mass airflow sensor removed. I believe the ecu will ignore the unplugged air mass and look at the tps signal as the deflaut..
I forgot about those Vac lines. I think I will just reinstall everything so the vacuum works as designed. Thank you very much everyone. Will keep you posted once the parts arrive.
Guys if the MAF doesn't sense air flow it will/possibly set a fault code (eng light). Easily removed. It will run but possibly rough. The ECU will use TPS but this works with the MAF to give a smooth idle control. Maybe best to reinstall plenum's I think. Just my thoughts
Having and an MAF fail on my Z4 years ago and last summer on my 95 355, I'd say "run rough" is a serious understatement. Neither car would idle and needed constant throttle manipulation to run at all. You aren't going to diagnose a problem like this with the plenums off, IMO.
Yup that’s whats gonna happen. I am still waiting for John K to give me the old told you so on about page two to check all the plugs instead of just the 1 side. All that stubbornness from me just because I did not want to take off that pretty Ferrari logo spark plug cover I guess Sorry John
LOL! I just want to see you get it running correctly. Of course, it's pretty much time to put it away for the winter, at least for use top down, spider drivers.
Ya no kidding Hellish summer for work Supposedly we had more rain this summer than has ever been recorded Trying to buiild roads between showers was a scheduling nightmare to say the least. Looking forward to our trip to Phoenix area and visit with Robb. Never thought I would look forward to snow but right now the sooner it comes the sooner is spring
Update Getting close to pulling engine. Thinking it’s the cam timing will update when I know, hopefully nothing major Stay tuned
Image Unavailable, Please Login Image Unavailable, Please Login First picture I think is where the engine was timed properly, you can see the marks on the sprocket on bank 5-8 are close, and at this time the cam timing marks on this bank are right on their marks but on 1-4 are 2 teeth out. They are also about the 2 teeth from being close to their respective timing marks The second Picture is when I lined up the old marks on the 5-8 bank. This was ware this bank was timed, the timing marks are now slightly off but within 1 0r 2 mm. The bank 1-4 is now even more out of time. So which belt jumped is the question for now. My guess is the 1-4 bank because it was not running on this bank and also the tensioner is extended way more than it should be. What does not make sense to me is I think logically that the 5-8 bank jumped thereby advancing the 1-4 bank. Obviously I will know as soon as retime the engine. But for sure 1 bank jumped 2 teeth somehow and I do not think I have any engine damage. What’s the brotherhood think about engine damage or what they think happened.
Image Unavailable, Please Login Image Unavailable, Please Login Here is some pictures of the tensioners My last 2 engine outs I tighten the bearings with no torque wrench but tight This time I figured I would torque everything to spec. I also tightened the belts to spec with a belt tensioner. This time I will tighten them tighter because something must have slipped
Went back and reread the thread from the beginning. I can see why I was getting different signals. The Leonardo says bad crank sensor and the obd 2 says bad cam sensor. This makes sense if bank 1 jumped because the cam and crank will now get different results. It’s is just from my logic, which could be wrong, it seems that if the engine turns clockwise then the bank 2 looks like it would have jumped.
Maybe I'm looking at it wrong but if the marks on the cam sprockets on both banks are supposed to line up at the same crank position, and the marks on bank 2 do but bank 1 doesn't, then it would appear that on bank 1 both cams are advanced by the same amount. But if the belt skipped, i.e. engine turned but cams didn't, the cams should be retarded. For the 1-4 bank cams to be advanced the engine would have to be turning backwards. So, did the engine backfired when you were trying to figure this out? If I'm looking at this correctly and bank 1 is advanced, and by 2 teeth, then the intake would have opened like 20+ degrees too early and it's possible they hit the pistons. Maybe not enough to damage the pistons significantly, but perhaps enough to bend the intake valves. I think a ways back I mentioned it might be time to check compression or leak down. Paul has a point.
No it did not that’s exactly why it did not make sense. Although my wife just said it backfired once out the 1-4 side I will set cylinder 1 at TDC and then I will know for sure. But if it did not back fire and bank 5-8 is good then it seems bank 1 advanced which makes no sense but when I was driving it and it first happened it could have backfired before I had it at the house and was trying to diagnose. But in your opinion would a backfire on bank 1-4 with a loose cam belt advance bank 1-4??
Yes it’s easy to do a compression check and I will once I get it timed correctly. I think for both cams on bank one to advance 2 teeth during a backfire seems all most impossible. Something to think about though.
To me it would be more logical if bank 5-8 jumped thus retarding this bank. Does that not make more sense??
Inspect pistons through plug hole this will tell you everything. By the way. You can still have good comp with a slightly bent valve! Good spring pressure will assist in flexing the valve stem a little. And the valve stems are small on a 355. If you have bent valves you will see valve face marks on the piston crown. Ask me how I know!!! Luckily enough it wasn't my 355 this happened too but a muscle car I have
The car still not running? Bummer. My guess is installation error. When belt install is correct the belts don’t slip. A backfire won’t cause slip if install is correct. Old guys use to say to me "if you don't have time to do it right the 1st time, when are you going to find time to do it right the second time?" I took that to mean "don't screw up". I measure twice, cut once, then measure again. I'm the old guy now, and I'm still doing things the way the old guys said. If you think you did it right the 1st time it is much more likely your method is flawed than parts have failed. That is not a put down on you or a personal attack. I have just found when looking for blame I usually find it in front of the mirror.
