Missing at 2000rpm.
07-27-2003, 10:26 PM
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Missing at 2000rpm.
Hi Folks.
Better tell you the whole story.
One beautiful Friday night, stars were shining, not a cloud in the sky. Feeling fantastic and ready to party.
Cruising down to pick up my date for a hot night. Turned into her street and thats when the nightmare started. My little pride and joy started to buck and cut out and carry on. Then it would cut in and out, finally it died and i just had enough momentum to roll up in front of my ladies place.
Sitting there contemplating to myself, thinking, What the hell do i do now.
Anyway, bright idea. Bounded out of car, flowers in hand. Met my lady at the door. And said. "Hey babe, lets catch a Limo tonight, save me driving"
And guess what she said. " Aw, honey i want to go cruising in the Porsche.
Standing there thinking, What the hell do i do now. Anyway, came clean with what happened and we caught the Limo anyway.
Hey, and still had a fab night.
Ok, sorry. Back to the problem.
Next morning, tried to start it. Wind over no problems. Ok, i know what your thinking. "Did he stay the night". Yeah, i did.
Anyway. Hmmmm, whats the name of that song "Oh, what a night".
Sorry, side tracked.
Ummm. Yeah. Only way she would start was to pump the pedal, then hold it about 2500revs. Then it would just cut out as if i turned off the key, Did that all the time until i gave up.
How embarrasing, had to take my little baby home on a truck. Not a happy chappy.
Ooops. Before this all happened. One tank of fuel before, i changed to unleaded with lead replacer additive. Ran fine, then thought it was cheaper to run on the normal lead free super. So next tank, filled her up with super again and used and octane booster. That was the Friday arvo.
So, i am assuming that was the cause.
Replaced fuel filter, Hey, ran great for about 30 minutes then played up.
Drained fuel tank, replaced fuel with lead free super. Put on another fuel filter.
Oh, sorry. The playing up bit was, it was missing at around 2000revs.
Before and after was fine, lacked the original torque though.
Ran out of time, so put it into the shop. Mechanic said when he pick up the car it was kicking and bucking and wouldn't go over 60kms. Just between you and me, i think it was a reaction of going to "The Shop".
Anyway, went away for the week, came home Friday and guess what. Damn, not fixed. He done a carbon flush of the motor, cleaned fuel filter,
Checked electrical, replaced coil lead. Plus a general check.
Oh, i must add, he is not a Porsche specialist.
Could not check brain as did not have specs and did not have a diagnostic machine.
Got it back to the stage of a few misses at around 2000revs.
Have been putting up with it. Strange though, starts perfect and then go out and it would run fine. Other times starts perfect, runs like crap.
Then stopped at lights, it would buck a couple of times and cut out, but would start straight away and run perfect for a couple of days.
Am going to replace fuel pump check valve today.
I think it is more electrical.
Help me guys, i am pulling my hair out here. Don't want to take her back to the shop.
Have checked vacuum lines, they seem to be ok. I think. Oh yes, something different this morning. Went to pull out of intersection and half way across she bucked a couple of times and died, pulled over to the curb and went to start her and big backfire, frightened the crap out of me. Started fine and runs great, till next time.
Any help appreciated. I live in Queensland,Australia folks.
Gary.
81, 928.
Better tell you the whole story.
One beautiful Friday night, stars were shining, not a cloud in the sky. Feeling fantastic and ready to party.
Cruising down to pick up my date for a hot night. Turned into her street and thats when the nightmare started. My little pride and joy started to buck and cut out and carry on. Then it would cut in and out, finally it died and i just had enough momentum to roll up in front of my ladies place.
Sitting there contemplating to myself, thinking, What the hell do i do now.
Anyway, bright idea. Bounded out of car, flowers in hand. Met my lady at the door. And said. "Hey babe, lets catch a Limo tonight, save me driving"
And guess what she said. " Aw, honey i want to go cruising in the Porsche.
Standing there thinking, What the hell do i do now. Anyway, came clean with what happened and we caught the Limo anyway.
Hey, and still had a fab night.
Ok, sorry. Back to the problem.
Next morning, tried to start it. Wind over no problems. Ok, i know what your thinking. "Did he stay the night". Yeah, i did.
Anyway. Hmmmm, whats the name of that song "Oh, what a night".
Sorry, side tracked.
Ummm. Yeah. Only way she would start was to pump the pedal, then hold it about 2500revs. Then it would just cut out as if i turned off the key, Did that all the time until i gave up.
How embarrasing, had to take my little baby home on a truck. Not a happy chappy.
Ooops. Before this all happened. One tank of fuel before, i changed to unleaded with lead replacer additive. Ran fine, then thought it was cheaper to run on the normal lead free super. So next tank, filled her up with super again and used and octane booster. That was the Friday arvo.
So, i am assuming that was the cause.
Replaced fuel filter, Hey, ran great for about 30 minutes then played up.
Drained fuel tank, replaced fuel with lead free super. Put on another fuel filter.
Oh, sorry. The playing up bit was, it was missing at around 2000revs.
Before and after was fine, lacked the original torque though.
Ran out of time, so put it into the shop. Mechanic said when he pick up the car it was kicking and bucking and wouldn't go over 60kms. Just between you and me, i think it was a reaction of going to "The Shop".
Anyway, went away for the week, came home Friday and guess what. Damn, not fixed. He done a carbon flush of the motor, cleaned fuel filter,
Checked electrical, replaced coil lead. Plus a general check.
Oh, i must add, he is not a Porsche specialist.
Could not check brain as did not have specs and did not have a diagnostic machine.
Got it back to the stage of a few misses at around 2000revs.
Have been putting up with it. Strange though, starts perfect and then go out and it would run fine. Other times starts perfect, runs like crap.
Then stopped at lights, it would buck a couple of times and cut out, but would start straight away and run perfect for a couple of days.
Am going to replace fuel pump check valve today.
I think it is more electrical.
Help me guys, i am pulling my hair out here. Don't want to take her back to the shop.
Have checked vacuum lines, they seem to be ok. I think. Oh yes, something different this morning. Went to pull out of intersection and half way across she bucked a couple of times and died, pulled over to the curb and went to start her and big backfire, frightened the crap out of me. Started fine and runs great, till next time.
Any help appreciated. I live in Queensland,Australia folks.
Gary.
81, 928.
07-27-2003, 11:17 PM
#3
Nordschleife Master
So it's an '81 and you're in Australis. That means a CIS system, right? That'd have eight individual lines, maybe 3mm each running from the fuel distributor on the rear of the engine.
These area real pain to diagnose once they go bad. The first thing I'd do is used someTechron injector cleaner. Run the whole tank through. If it doesn't act right, and I expect it won't, then take it to a BMW mechanic, or maybe VW. These Bosch systems were on a lot of cars in the 70's and 80's.
You'll need to have the fuel pressures and pump flow checked. Then that should isolate what, if anything, is wrong with the FI system. Check the email archives on this if you're interested in doing it yourself.
Something to check is for smooth action of the "control lever." Pull off the air filter housing and move the plate up and donw, gently. If it's sticky, then the distributor will need to be rebuilt. I mention this as it sounds like you're getting flooded with gas sometimes.
Then again, it could be ignition, but that wouldn't make it backfire occasionally.
These area real pain to diagnose once they go bad. The first thing I'd do is used someTechron injector cleaner. Run the whole tank through. If it doesn't act right, and I expect it won't, then take it to a BMW mechanic, or maybe VW. These Bosch systems were on a lot of cars in the 70's and 80's.
You'll need to have the fuel pressures and pump flow checked. Then that should isolate what, if anything, is wrong with the FI system. Check the email archives on this if you're interested in doing it yourself.
Something to check is for smooth action of the "control lever." Pull off the air filter housing and move the plate up and donw, gently. If it's sticky, then the distributor will need to be rebuilt. I mention this as it sounds like you're getting flooded with gas sometimes.
Then again, it could be ignition, but that wouldn't make it backfire occasionally.
07-27-2003, 11:57 PM
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Hey Gazz... I hope you don't have a catalytic converter...they don't like leaded fuel...If I'm not mistaken, they have a tendancy to plug up and you could have a problem with your o2 sensor causing your rough idle...good-luck
Bill
Bill
07-28-2003, 02:03 AM
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Your fuel distributor is slowly going bad. I think-
I had an '80 VW Jetta last year with the same Bosch K-Jetronic fuel injection system. This car was an airport car- a car parked for weeks at a time in the employee parking lot, and typically something that will start but will bring you little other joy otherwise. A good airport car is not something that attracts theives.
Well, I had to go to training in Miami last year for 5 weeks for my new airline. While I was there, on a Saturday, I decided to go to the mall and buy new running shoes. On the way back to the hotel, I decided to waste an '80's vintage Supra around a cloverleaf onto the Dolphin Expressway [The Jetta had a pretty serious suspension...], only to find my Jetta bucking and backfiring viciously half way around the curve.
I drove the car from Miami to Orlando a few weeks later...on the way home, not only did the brake line blow out [no brakes....I managed to stop safely], but it slowly lost power as I drove on the expressway. At one point, I was down to 70 km/h on a road normaly traveled at 130! I would pull over, pull the fuel pump relay, and it would run better for a few miles. I nursed the car home this way.
Well, I got it home and changed the fuel pump, thinking it was bad. I never took the car on any long drives on the e-way after that...a girlfriend of one of my neighbors was interested in buying it, and since I liked her
[I had previously "liked" her on one specific occasion~]
I sold it to her WAY cheap, telling her about all the problems. She found a mechanic, and spent not a small amount of coin replacing the fuel distributor. It runs great now, from what I've heard. The fuel distributor is a
V E R Y
sensitive part to any sort of fuel contamination. If you think that leaded fuel may have done this, then you are wrong, but if anything got past your filter [and some things can...] then you need to replace this. Since the fuel distributor's plunger is moved by a metal part that is attached to a flap that is effected by air flow, it is possible that if some sort of contamination has taken place....that the plunger can't move correctly. DO NOT remove the plunger from the distributor block!
-In 1984, I was a high school senior, and I bought my first car: A VW Golf. 1588 cc's, Bosch K-Jetronic, and 78 hp. It weighed in at barely 1780 lbs....which meant that the engine had a lot of torque for the weight and the little car had a reputation around school for being quick. And then I had a fight with my girlfriend. She discovered my car at a house party a week later, and in a fit of rage, decided that my car would run better with 2 liters of Mountain Dew [a soda drink sold in the US] in its gas tank. I wound up replacing two injectors and the fuel distributor. Great thing for a high school student who worked at Little Caesars Pizza in 1984 and contemplating college tuition- a $300 repair bill.
[Sad thing/Not so sad thing- you decide: Most of my close friends knew right away she did this. I didn't find out until a year later- she was dating a muscle-head at the time who would have easily hospitalized/ended my 6' 120 pound/ 1.83m/50 kg frame...they said they were looking out for me~]
CIS is better than L-Jetronic or LH [motronic] in that it is simpler...but when it f*cks up...it can be more difficult to diagnose. I wish you the best....
Please don't hit a 'roo with your car! My brother just tore up his VW Golf hitting a damn deer-
Normy!
'85 S2 5 Speed
I had an '80 VW Jetta last year with the same Bosch K-Jetronic fuel injection system. This car was an airport car- a car parked for weeks at a time in the employee parking lot, and typically something that will start but will bring you little other joy otherwise. A good airport car is not something that attracts theives.
Well, I had to go to training in Miami last year for 5 weeks for my new airline. While I was there, on a Saturday, I decided to go to the mall and buy new running shoes. On the way back to the hotel, I decided to waste an '80's vintage Supra around a cloverleaf onto the Dolphin Expressway [The Jetta had a pretty serious suspension...], only to find my Jetta bucking and backfiring viciously half way around the curve.
I drove the car from Miami to Orlando a few weeks later...on the way home, not only did the brake line blow out [no brakes....I managed to stop safely], but it slowly lost power as I drove on the expressway. At one point, I was down to 70 km/h on a road normaly traveled at 130! I would pull over, pull the fuel pump relay, and it would run better for a few miles. I nursed the car home this way.
Well, I got it home and changed the fuel pump, thinking it was bad. I never took the car on any long drives on the e-way after that...a girlfriend of one of my neighbors was interested in buying it, and since I liked her
[I had previously "liked" her on one specific occasion~]
I sold it to her WAY cheap, telling her about all the problems. She found a mechanic, and spent not a small amount of coin replacing the fuel distributor. It runs great now, from what I've heard. The fuel distributor is a
V E R Y
sensitive part to any sort of fuel contamination. If you think that leaded fuel may have done this, then you are wrong, but if anything got past your filter [and some things can...] then you need to replace this. Since the fuel distributor's plunger is moved by a metal part that is attached to a flap that is effected by air flow, it is possible that if some sort of contamination has taken place....that the plunger can't move correctly. DO NOT remove the plunger from the distributor block!
-In 1984, I was a high school senior, and I bought my first car: A VW Golf. 1588 cc's, Bosch K-Jetronic, and 78 hp. It weighed in at barely 1780 lbs....which meant that the engine had a lot of torque for the weight and the little car had a reputation around school for being quick. And then I had a fight with my girlfriend. She discovered my car at a house party a week later, and in a fit of rage, decided that my car would run better with 2 liters of Mountain Dew [a soda drink sold in the US] in its gas tank. I wound up replacing two injectors and the fuel distributor. Great thing for a high school student who worked at Little Caesars Pizza in 1984 and contemplating college tuition- a $300 repair bill.
[Sad thing/Not so sad thing- you decide: Most of my close friends knew right away she did this. I didn't find out until a year later- she was dating a muscle-head at the time who would have easily hospitalized/ended my 6' 120 pound/ 1.83m/50 kg frame...they said they were looking out for me~]
CIS is better than L-Jetronic or LH [motronic] in that it is simpler...but when it f*cks up...it can be more difficult to diagnose. I wish you the best....
Please don't hit a 'roo with your car! My brother just tore up his VW Golf hitting a damn deer-
Normy!
'85 S2 5 Speed
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07-28-2003, 02:33 PM
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Everyone is wrong above. Please remove and check the green lead wire between the brain and your distributor. Check with multimeter. I will bet there will be a place where its cracked through and the wires are shorting onto themselves. Make sure you twist and bend the wire around a bit.
Please note that recently Porsche made a bunch of bad green wires and they will make the car run just as bad as your old green wire. Make sure the new green wire is tested before shipping to you.
Please note that recently Porsche made a bunch of bad green wires and they will make the car run just as bad as your old green wire. Make sure the new green wire is tested before shipping to you.
07-28-2003, 02:37 PM
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Originally posted by Curt
Everyone is wrong above.
Everyone is wrong above.
Last edited by Randy V; 07-29-2003 at 03:32 PM.
07-29-2003, 04:59 AM
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Hey guys.
Thanks for the replies. Am going to wittle through and check everything you have suggested. Geez, don't give me too much to check. But then i do want to get it right. I would rather go through the lot, least i know then.
Have replaced fuel filter and check valve in fuel pump. Seems to be a bit better, but then it can go for a few days running perfect, then play up again.
oh, something i forgot to mention in my first post. The mechanic played with the fuel mixture too. Don't know why as it was never touched, as car was running perfect before all this started. I think he was just guessing and hoping to jag the problem.
Anyway i will keep on plugging.
I will keep you posted and let you know when i find the problem, hopefully.
Seeya.
Gary
Thanks for the replies. Am going to wittle through and check everything you have suggested. Geez, don't give me too much to check. But then i do want to get it right. I would rather go through the lot, least i know then.
Have replaced fuel filter and check valve in fuel pump. Seems to be a bit better, but then it can go for a few days running perfect, then play up again.
oh, something i forgot to mention in my first post. The mechanic played with the fuel mixture too. Don't know why as it was never touched, as car was running perfect before all this started. I think he was just guessing and hoping to jag the problem.
Anyway i will keep on plugging.
I will keep you posted and let you know when i find the problem, hopefully.
Seeya.
Gary
07-29-2003, 01:52 PM
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Gary, check that green wire first. It wont take you long to figure out if its good or not. Its an easy 10-20 minute job. You may have to remove the distributor hold down bolt and rotate the distributor clockwise to get to the tiny screws that hold the wire connection onto the distributor. You will also have to remove the distributor cap. Easiest way is to unplug plug wires 5-8 on the cap. pop the cap off and let hang to the side. Then remove that little plate cover for the wires. Connector will pull right out.
