1979 930 Pinging but why now?

Porschepilot79 · 10:06 PM

Hello friends, My 930 was pinging once im on the boost. the motor was lowered to be worked on with seals and valve adjustment and new hoses but after the driving the car with the changes it pinged a lot. What could have been altered to do this? Any vacuum hoses maybe that control fuel or something come lose?? I hope I didnt harm the engine from it being for 5 seconds? I didn't notice anything abnormal so far?

Thanks George

JMA-RUF · 03-12-2009, 10:54 PM

If you had all new hoses fitted and it just started, check for vacuum leaks OR take it back to the mechanic and complain your head off!

If he hasn't been diligent and careful with vacuum connections, he should be made to double check it for you!

cole930 · 03-13-2009, 05:06 AM

George,

A few quick checks would be: Ck that the vacuum lines for the distributor are connected correctly and that timing advance/retard are working.

That politically correct Calif. green gas sucks so make sure you have as high a octane rating
fuel as you can find.

Reset the timing, make sure you know what it should be ie. US, Euro, or Calif. the timing requirements are different for each.

Cole

beepbeep · 06:37 AM

Check AFR's, igniton timing and (edit) boost. There is 95% chance that one of three is off. If all are in check, you might have carbon piece lodged in some of cylinders. Also, a single clodged injector won't show up on AFR, it will only show up as high HC on exhaust analyzer or as hole in the piston.

Miguel Antonett · 03-13-2009, 06:15 AM

Check the connection from the IC to the WG.

How much boost are you running?

Octanes?

Porschepilot79 · 03-13-2009, 07:16 AM

Quote:

Originally Posted by JMA-RUF

If you had all new hoses fitted and it just started, check for vacuum leaks OR take it back to the mechanic and complain your head off!

If he hasn't been diligent and careful with vacuum connections, he should be made to double check it for you!

Well hes a Porsche nut freind of mine who works on Porsche on the weekend haha. He may have missed something but what??

Porschepilot79 · 03-13-2009, 07:19 AM

Quote:

Originally Posted by cole930

George,

A few quick checks would be: Ck that the vacuum lines for the distributor are connected correctly and that timing advance/retard are working.

That politically correct Calif. green gas sucks so make sure you have as high a octane rating
fuel as you can find.

Reset the timing, make sure you know what it should be ie. US, Euro, or Calif. the timing requirements are different for each.

Cole

Oh I have a Electromotive 1 so its a crack fire system. I do have a 101 station but it should not need that unless I would have run more then a 1 bar? Could the boost have changed since it does feel stronger?

Porschepilot79 · 03-13-2009, 07:22 AM

Quote:

Originally Posted by beepbeep

Check AFR's, igniton timing and (edit) boost. There is 95% chance that one of three is off. If all are in check, you might have carbon piece lodged in some of cylinders. Also, a single clodged injector won't show up on AFR, it will only show up as high HC on exhaust analyzer or as hole in the piston.

Oh wow well, I will need to go through those items and then look for high HC as well? What should the HC be and what is high?

Porschepilot79 · 03-13-2009, 07:24 AM

Quote:

Originally Posted by Miguel Antonett

Check the connection from the IC to the WG.

How much boost are you running?

Octanes?

How does the IC connect to the WG? Is it a vacuum hose? I dont know how much boost it is just yet as im learning all about my car. I purchase with a lot of nice things done to it.

Miguel Antonett · 03-13-2009, 08:48 AM

There is a hose that goes from the intercooler (IC) to the waste gate (WG). Depending on the mods on the car, that hose could go to different places on the IC system; however, it will always go to the WG. Start from the WG and follow it back to see where it lands and check for leaks. Also be sure that it is connected to the proper port on the WG. Again, depending on the mods (if different than OEM WG) the connecting port could be on top or bottom of the WG; one port is "in" for + pressure and the other is "out" for exhaust of the WG. If those are backward, then the WG is not opening getting an overboost condition knocking/peening and possibly lots of $s if not fix ASAP..

beepbeep · 03-13-2009, 09:25 AM

Quote:

Originally Posted by Porschepilot79

Oh wow well, I will need to go through those items and then look for high HC as well? What should the HC be and what is high?

You could also dismount the injectors and send them for testing/cleaning. But to begin with, check that your ignition, AFR's and air plumbing are OK. If everything checks out you can start hunting for more peculiar issues (like clogged injectors).

mark houghton · 03-13-2009, 11:02 AM

Quote:

Originally Posted by Porschepilot79

Oh I have a Electromotive 1 so its a crack fire system. I do have a 101 station but it should not need that unless I would have run more then a 1 bar? Could the boost have changed since it does feel stronger?

Well there's your problem! While she was away being diddled by a stranger, she became a crack head and is addicted to the old Peruvian snow.

I'm with most everyone else here: (1) ignition timing is way off (2) vacuum leaks (affecting timing) or (3) crappy fuel. I wouldn't be running up the boost until you sort it out.

WERK I · WERK I's Garage

Like Goran said, check the simple things first, hoses, timing. If it's an Electromotive HPV-1 twin-plug, check plug wire hookups too. Make sure both timing modules are in sync.

Porschepilot79 · 09:24 AM

Quote:

Originally Posted by Miguel Antonett

There is a hose that goes from the intercooler (IC) to the waste gate (WG). Depending on the mods on the car, that hose could go to different places on the IC system; however, it will always go to the WG. Start from the WG and follow it back to see where it lands and check for leaks. Also be sure that it is connected to the proper port on the WG. Again, depending on the mods (if different than OEM WG) the connecting port could be on top or bottom of the WG; one port is "in" for + pressure and the other is "out" for exhaust of the WG. If those are backward, then the WG is not opening getting an overboost condition knocking/peening and possibly lots of $s if not fix ASAP..

Wow the WG hose it open! I took pictures of how it is now and maybe you guys can tell me how it should be routed?

WERK I · WERK I's Garage

That'll do it.
Didn't you get some sort of sign of over-boost reading on your gauge when the engine started pinging?

The hose is usually routed up to a fitting on the IC.

spuggy · 03-14-2009, 09:24 AM

Quote:

Originally Posted by Porschepilot79

Wow the WG hose it open! I took pictures of how it is now and maybe you guys can tell me how it should be routed?

Here is a pic from the WG to the engine compartment

If that hose comes off the top of the factory WG body, it should be "open to atmosphere" so that air on top of the diaphragm is not compressed, allowing free movement of the WG valve. It is usually routed to the airbox or otherwise arranged so that small birds don't nest in it...

If that hose comes off the middle (side) of the factory WG body, it's supposed to be the boost signal, and should be connected to the pressurized portion of the intake somewhere. Without it connected, there won't be any boost regulation (WG won't open because it'll never "see" the boost).

If it's an aftermarket WG, check what the manufacturer says the ports do...

Porschepilot79 · 03-14-2009, 09:29 AM

WG hose coming up to the engine compartment.

Picture of WG

Picture of with only outlet I can find on IC but the spot is taken with another hose going to what I think is a throttle body??

Here is where it goes

beepbeep · 03-14-2009, 09:30 AM

What boost did your gauge register just prior to knock? There is a overboost protection switch that will trip the fuel pump(s) relay(s) once boost goes past 1.1 bar (or so). If switch is bypassed and wastegate hose is cracked/removed the turbo will overboost and engine will probably ping.

beepbeep · 09:50 AM

Edit: just saw your pics. Oh dear.

If the blue hose connected to wastegate side (not the top one with missing banjo-nipple, where did that one go?) is open, turbo will deadhead and (if safety switch is working) you will expirience "dash-in-your-face" syndrom. If somebody bypassed the switch (which many regrettably do when installing 1.0 bar spring), you will have no limit whatsover.

Check if hose going to side of WG is disconnected. If it is, check with the shop that did the engine work. They might have missed the hose or snapped it when lowering the engine.

Also, do the compression and leakdown test. Hopefully, your pistons are fine but if they are not you might want to talk with the shop.

Porschepilot79 · 03-14-2009, 09:33 AM

Quote:

Originally Posted by WERK-I

That'll do it.
Didn't you get some sort of sign of over-boost reading on your gauge when the engine started pinging?

The hose is usually routed up to a fitting on the IC.

The factory gauge would go to 1 bar befor so it was the same since that was the max anyhow. Only this time it was pinging since it was go past one bar.