Spark Plugs Almost instantly Get Fouled Up W/Carbon |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
Spark Plugs Almost instantly Get Fouled Up W/Carbon |
JohnWayne |
Aug 19 2012, 06:43 PM
Post
#1
|
Newbie Group: Members Posts: 23 Joined: 18-July 12 From: Colorado Springs,CO Member No.: 14,691 Region Association: None |
I can't figure out why the spark plugs are getting fouled up with carbon within 2 minutes of idling.
Thanks in adnvance |
VaccaRabite |
Aug 19 2012, 06:58 PM
Post
#2
|
En Garde! Group: Admin Posts: 13,456 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
What engine? Old and tired? fresh rebuild?
What fuel system? Djet? Ljet? Carbs? EFI? What kind of gas? What kind of plugs? Tell us more and we will help. |
JohnWayne |
Aug 19 2012, 07:04 PM
Post
#3
|
Newbie Group: Members Posts: 23 Joined: 18-July 12 From: Colorado Springs,CO Member No.: 14,691 Region Association: None |
it's a 73 1.7L fuel injection djet. It has premium gas in now and has the OE Bosch Plugs. The engine has new rings and that's about it.
|
timothy_nd28 |
Aug 19 2012, 07:04 PM
Post
#4
|
Advanced Member Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest |
Can you post some pics of your setup and your fouled plugs?
|
JohnWayne |
Aug 19 2012, 07:15 PM
Post
#5
|
Newbie Group: Members Posts: 23 Joined: 18-July 12 From: Colorado Springs,CO Member No.: 14,691 Region Association: None |
I Also have brand new Bosch Wires
Attached image(s) |
brant |
Aug 19 2012, 08:17 PM
Post
#6
|
914 Wizard Group: Members Posts: 11,632 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
are the rings seated?
perhaps the CHT or MPS is out and its runing uber rich? its got to be fuel or oil. |
timothy_nd28 |
Aug 20 2012, 12:29 PM
Post
#7
|
Advanced Member Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest |
Are all the plugs the same way? When was the last time you did a valve adjustment? The first thing in order would be a compression test (engine warm)
|
McMark |
Aug 20 2012, 02:20 PM
Post
#8
|
914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
A wideband O2 sensor would really help diagnose this. (IMG:style_emoticons/default/wink.gif)
|
SLITS |
Aug 20 2012, 03:16 PM
Post
#9
|
"This Utah shit is HARSH!" Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None |
1.) is the black wet? = oil fouled
2.) is the black just sooty? = way rich |
Rand |
Aug 20 2012, 03:22 PM
Post
#10
|
Cross Member Group: Members Posts: 7,409 Joined: 8-February 05 From: OR Member No.: 3,573 Region Association: None |
If it gets that bad in two minutes, I would think it's got to be oil. If it was just uber rich (rich enough to do THAT) it would be tough getting it to idle well at all, and you'd have to smell it in the exhaust.
What kind of smoke are you getting out the exhaust pipe? |
JohnWayne |
Aug 20 2012, 03:40 PM
Post
#11
|
Newbie Group: Members Posts: 23 Joined: 18-July 12 From: Colorado Springs,CO Member No.: 14,691 Region Association: None |
I figured out the timing was off, so now it's not smoking anymore. It drives really smooth now, but the plugs still get fouled up enough that it won't start after about 20 min of driving. The idle stays around 1000 rpm.
I was also wondering about the ECU. My dad got it from this porsche mechanic and i don't know if it's for a 2.0L or 1.7L. I don't know if that would make a difference in richness or not. I got a Manifold Pressure Sensor from the same guy and also don't know if that is for a 1.7L. If the ECU and MPS is not for the 1.7L would it cause the richness i'm getting? |
SLITS |
Aug 20 2012, 04:16 PM
Post
#12
|
"This Utah shit is HARSH!" Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None |
I figured out the timing was off, so now it's not smoking anymore. It drives really smooth now, but the plugs still get fouled up enough that it won't start after about 20 min of driving. The idle stays around 1000 rpm. I was also wondering about the ECU. My dad got it from this porsche mechanic and i don't know if it's for a 2.0L or 1.7L. I don't know if that would make a difference in richness or not. I got a Manifold Pressure Sensor from the same guy and also don't know if that is for a 1.7L. If the ECU and MPS is not for the 1.7L would it cause the richness i'm getting? Read this: D-Jet Trouble Shooting |
JohnWayne |
Aug 20 2012, 07:18 PM
Post
#13
|
Newbie Group: Members Posts: 23 Joined: 18-July 12 From: Colorado Springs,CO Member No.: 14,691 Region Association: None |
I put a different MPS in and I think that was the problem because the spark plugs aren't that bad anymore. I just need to break in the new rings now.
Thanks for all the answers |
Rockaria |
Aug 21 2012, 11:52 AM
Post
#14
|
ZippidyDoDah... Group: Members Posts: 817 Joined: 2-May 03 From: Southwest, USA Member No.: 645 Region Association: None |
I put a different MPS in and I think that was the problem because the spark plugs aren't that bad anymore. I just need to break in the new rings now. Thanks for all the answers Quick question? Before your fixes, Did it get so bad that the car died while running and would not restart untill the plugs were cleaned? |
JohnWayne |
Aug 21 2012, 12:36 PM
Post
#15
|
Newbie Group: Members Posts: 23 Joined: 18-July 12 From: Colorado Springs,CO Member No.: 14,691 Region Association: None |
yeah
|
messix |
Aug 21 2012, 12:37 PM
Post
#16
|
AKA "CLUTCH KILLER"! Group: Members Posts: 6,995 Joined: 14-April 05 From: between shit kickers and pinky lifters/ puget sound wa.north of Seattle south of Canada Member No.: 3,931 Region Association: Pacific Northwest |
pull the dip stick and smell the oil to see if it smells like gas, if it does change the oil and filter now!
running rich can wash the oil off the cylinders and gall the rings and cylinders and then the rings will never break in. |
Rockaria |
Aug 21 2012, 01:40 PM
Post
#17
|
ZippidyDoDah... Group: Members Posts: 817 Joined: 2-May 03 From: Southwest, USA Member No.: 645 Region Association: None |
yeah Well Howdy Doody! I bet that is my exact problem as well. My MPS no longer has the epoxy on it and when I put back the 270 Ohm resistor I bet the combination was way too rich. Who knows what the PO has it set to. Thanks! Oil Change is on the schedule! ( I have new rings as well.) |
Cap'n Krusty |
Aug 21 2012, 03:29 PM
Post
#18
|
Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
Two issues jump right out. Premium fuel. It's pretty likely you don't need it, and it's less volatile than the lower grades, meaning it burns more slowly. Bosch wires: There's a reason Porsche has never used them as a factory part. They're junk. Granted, you have other issues, but these need to be fixed.
The Cap'n |
Lo-Fi Version | Time is now: 2nd June 2024 - 11:59 AM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |