| Author |
Message |
busdaddy
Samba Member
Joined: February 12, 2004
Posts: 53231
Location: Surrey B.C. Canada, but thinking of Ukraine
|
 Posted: Sat Oct 11, 2025 6:36 pm Post subject: Re: Official Fuel injection questions thread |
 |
|
| tbenne wrote: |
Thanks for the reply. I will check out the bay window forum.
What does "CO" stand for? |
Carbon monoxide, it’s the level of gases in the exhaust measured by an exhaust analyzer, the scientific way to set mixture.
_________________
Rust NEVER sleeps and stock never goes out of style.
Please don't PM technical questions, ask your problem in public so everyone can play along. If you think it's too stupid post it here
Stop dead photo links! Post your photos to The Samba Gallery!
Слава Україні! |
|
| Back to top |
|
 |
EverettB 
Administrator
Joined: April 11, 2000
Posts: 71996
Location: Phoenix 602
|
|
| Back to top |
|
|
tbenne
Samba Member
Joined: December 16, 2011
Posts: 3
Location: Nova Scotia
|
|
| Back to top |
|
|
jwms
Samba Member
Joined: October 23, 2015
Posts: 89
Location: Fort Worth, Texas
|
| Posted: Wed Oct 29, 2025 12:38 pm Post subject: Re: Official Fuel injection questions thread |
|
|
EGR Filter or Not?
'79 Beetle Convertible
My EGR lower tubing was removed by a PO and the filter is gone. The top of the lower tube is crushed closed and the muffler flange has been welded closed.
The questions are:
Is it worth buying the filter and going back original, or is the way it is set up now good for performance/economy, etc.?
and,
The filter is available to buy, but I see there is also an "elbow" tube for sale. Do I need to purchase both of these if I go back with the filter or do the tubes on the filter go from the upper mount to the muffler?
A good picture of a complete original lower area would be beneficial...
_________________
'72 Westy Camper Tin-Top-Project
'72 Westy Camper Tin-Top-Complete
'79 Tri-Color Black 'Vert'-Fuel Injected-Complete
'29 Ford Tudor Sedan |
|
| Back to top |
|
|
jwms
Samba Member
Joined: October 23, 2015
Posts: 89
Location: Fort Worth, Texas
|
| Posted: Wed Oct 29, 2025 12:49 pm Post subject: Re: Official Fuel injection questions thread |
|
|
EGR Filter or Not?
'79 Beetle Convertible
I just had a thought about this:
The left side of the muffler is lower than the right side. Could it be that the exhaust tubes (heater box) on one side or the other was hit and bent, which caused the lower EGR tube to break and therefore it was taken off and sealed up?
Thoughts on this?
_________________
'72 Westy Camper Tin-Top-Project
'72 Westy Camper Tin-Top-Complete
'79 Tri-Color Black 'Vert'-Fuel Injected-Complete
'29 Ford Tudor Sedan |
|
| Back to top |
|
|
busdaddy
Samba Member
Joined: February 12, 2004
Posts: 53231
Location: Surrey B.C. Canada, but thinking of Ukraine
|
| Posted: Wed Oct 29, 2025 2:32 pm Post subject: Re: Official Fuel injection questions thread |
|
|
The filter likely rotted out, it's not uncommon. The wilting exhaust may be from an offroad excursion, or maybe just wasn't hed up straight when all the nuts were tightened.
The EGR does reduce combustion chamber temps at speed, but a Beetle doesn't work hard enough to damage anything like a bus does, if you don't have to smog leaving it disconnected is likely the better option. It still looks the part from above. If you want it to look 100% correct install the filter but leave the port on the muffler blocked, no worries about it rusting out or leaking like that.
You might want to replace the gasket where the valve meets the plenum with a solid one, that eliminated the chances of vacuum leaks from a faulty valve.
_________________
Rust NEVER sleeps and stock never goes out of style.
Please don't PM technical questions, ask your problem in public so everyone can play along. If you think it's too stupid post it here
Stop dead photo links! Post your photos to The Samba Gallery!
Слава Україні! |
|
| Back to top |
|
|
jwms
Samba Member
Joined: October 23, 2015
Posts: 89
Location: Fort Worth, Texas
|
| Posted: Wed Oct 29, 2025 2:38 pm Post subject: Re: Official Fuel injection questions thread |
|
|
Thanks again, Busdaddy!
It's always run pretty good; I was thinking of replacing it for posterity...
And we don't smog...
_________________
'72 Westy Camper Tin-Top-Project
'72 Westy Camper Tin-Top-Complete
'79 Tri-Color Black 'Vert'-Fuel Injected-Complete
'29 Ford Tudor Sedan |
|
| Back to top |
|
|
jwms
Samba Member
Joined: October 23, 2015
Posts: 89
Location: Fort Worth, Texas
|
| Posted: Wed Oct 29, 2025 2:40 pm Post subject: Re: Official Fuel injection questions thread |
|
|
Oh, but if I did replace it, is it just the filter part, or also the other "elbow" too?
_________________
'72 Westy Camper Tin-Top-Project
'72 Westy Camper Tin-Top-Complete
'79 Tri-Color Black 'Vert'-Fuel Injected-Complete
'29 Ford Tudor Sedan |
|
| Back to top |
|
|
jwms
Samba Member
Joined: October 23, 2015
Posts: 89
Location: Fort Worth, Texas
|
| Posted: Wed Oct 29, 2025 2:51 pm Post subject: Re: Official Fuel injection questions thread |
|
|
I'm trying to wrap my head around the possible faulty valve. The diaphragm here on this one is still good (hold vacuum and I can hear movement), believe it or not. If the valve faulted open, there's no place for the plenum to get the extra air, as the valve body is sealed to the atmosphere.
The EGR light on the speedo is "on" when starting and immediately goes out. I would say that is normal. I don't know what the light "on" is signifying (what fault), when there is a failure. I'm assuming there's a microswitch in there if it doesn't operate when it is supposed to.
_________________
'72 Westy Camper Tin-Top-Project
'72 Westy Camper Tin-Top-Complete
'79 Tri-Color Black 'Vert'-Fuel Injected-Complete
'29 Ford Tudor Sedan |
|
| Back to top |
|
|
busdaddy
Samba Member
Joined: February 12, 2004
Posts: 53231
Location: Surrey B.C. Canada, but thinking of Ukraine
|
| Posted: Wed Oct 29, 2025 3:31 pm Post subject: Re: Official Fuel injection questions thread |
|
|
The light is controlled by that box mid way in the speedo cable in the trunk, it turns on the light when the service interval is due, 30K miles IIRC. Actual system health has no bearing on what the light does, it's strictly a reminder to have the dealer change the filter.
The diaphragm may be OK now, but some day it could become a vacuum leak, if the system is disabled a solid gasket eliminates all possible points of failure.
From the gallery:
_________________
Rust NEVER sleeps and stock never goes out of style.
Please don't PM technical questions, ask your problem in public so everyone can play along. If you think it's too stupid post it here
Stop dead photo links! Post your photos to The Samba Gallery!
Слава Україні! |
|
| Back to top |
|
|
Maltboy!
Samba Member
Joined: June 17, 2006
Posts: 140
Location: Santa Fe, Texas
|
| Posted: Wed Oct 29, 2025 4:13 pm Post subject: Re: Official Fuel injection questions thread |
|
|
The gasses were corrosive enough to eat completely through the EGR valve pipe on my 76 bug. I got a used one to replace it, but I decided to weld the hole shut at the muffler connection. It looks 100% correct, but no gasses get through. I figure anything that could damage the EGR that badly couldn't be good for the engine. The car runs fine.
_________________
76 Super Beetle convertible, Ford Chrome Yellow - body-off restoration, 100% of work done by me
59 Beetle convertible, future project - 25,000 actual miles, original interior
Last edited by Maltboy! on Tue Dec 30, 2025 7:34 pm; edited 2 times in total |
|
| Back to top |
|
|
Lost69Convertible
Samba Member
Joined: July 29, 2020
Posts: 494
Location: Rhode Island
|
| Posted: Thu Oct 30, 2025 7:29 am Post subject: Re: Official Fuel injection questions thread |
|
|
Hi jwms,
My ‘79 had the EGR disconnected and plugged by the PO in the same manner as yours. My EGR intake tube was crimped closed below the tin. But it wasn’t completely sealed and this caused small backfires when I lifted my foot off the gas pedal quickly. I sealed it completely and the backfires stopped. My engine has been running great for 5 years with the EGR intake sealed.
I bought an EGR filter locally. I plan to clean it up and install it for a stock look underneath. I’ll leave the EGR intake pipe plugged/sealed.
_________________
1956 Beetle Ragtop: My Father's car
1969 Beetle Convertible: My first car. I loved it, I lost it, and I never got over it.
1979 Super Beetle Convertible |
|
| Back to top |
|
|
Maltboy!
Samba Member
Joined: June 17, 2006
Posts: 140
Location: Santa Fe, Texas
|
| Posted: Tue Dec 30, 2025 7:26 pm Post subject: Re: Official Fuel injection questions thread |
|
|
Hey busdaddy!
What's the best fix for failed SB PCV diaphragms? Does anyone make an aftermarket replacement?
_________________
76 Super Beetle convertible, Ford Chrome Yellow - body-off restoration, 100% of work done by me
59 Beetle convertible, future project - 25,000 actual miles, original interior |
|
| Back to top |
|
|
busdaddy
Samba Member
Joined: February 12, 2004
Posts: 53231
Location: Surrey B.C. Canada, but thinking of Ukraine
|
|
| Back to top |
|
|
|
