SaabCentral Forums banner

1 - 13 of 13 Posts

·
Registered
Joined
·
344 Posts
Discussion Starter #1
Ok, I noticed today when I accelerate hard like getting on the interstate; my 05 saab 95 check engine light flashes and puts up a pending p1300 but it never sets active because I am not always driving my car at 5k rpm. Wis directs me to replace spark plugs. Spark plugs are less then 1 year old. I have a new DIC which is a PPS part thats 3 months old. I have yet to check fuel pressure but I also am 100% sure my cat is bad. Rear o2 sesor is new and always reads the same number as the front sensor. I also have a p0420 that is active. Vehicle drives perfectly normal other then at 5k. Gonna run a semi permanent fuel pressure gauge to see what the fuel pressure is doing during the fault. Also did the catalyst test with the tech 2 which also reads low o2. Any other thoughts will be entertained... but I am pretty sure that is down to a restricted cat of fuel pump.
 

·
Registered
Joined
·
344 Posts
Discussion Starter #3
If your cat is clogged o2 values should be different?

Sent from my VOG-L29 using Tapatalk
Did you miss the part where I said "I KNOW MY CAT IS BAD" Front 02 should be switching from 200mv to 700mv... rear should be stable at 500mv. I am 50% blaming plugged cat, 50% blaming weak fuel pump. Both can cause this.
 

·
Registered
Joined
·
344 Posts
Discussion Starter #4
If the cat is melded front and rear o2 would read the same, but then it wouldn't be a plugged cat, more of a hollow one which would make me think fuel pump not keeping up with the demand. Or maybe the low o2 in the cat is making the pcm starve the vehicle of gas. A restricted cat will cause exhaust back pressure which would make less room for air/fuel leading to the same problem.
 

·
Registered
Joined
·
2,284 Posts
If your cat is actually plugged, you won't get more than base boost. Trust me, been through it twice now. Also, the PPS DIC could very well be suspect. I had one, lasted less than a year before completely dying. It wasn't until I got and SEM DIC that I realized how much the car was lagging with the PPS DIC.
 

·
Registered
Joined
·
344 Posts
Discussion Starter #6
If your cat is actually plugged, you won't get more than base boost. Trust me, been through it twice now. Also, the PPS DIC could very well be suspect. I had one, lasted less than a year before completely dying. It wasn't until I got and SEM DIC that I realized how much the car was lagging with the PPS DIC.
Normally I would accept this possibility, if my dic was more then just 2 months old I probally would accept it as a viable solution. Also the car runs perfectly fine, no symptoms or codes other then a p0420
And I tested 3 sem dics for my work and the car still behaved the same. 100% my cat is bad. From what I see in the scan tool its hallowed out. If the front and rear o2 sensors seitch at the same time (actully a couple milliseconds apart) tells me that cat aint working. But if a hole was melted in the middle of the cat allowing most exhaust to flow out with and outter ring of the cat was restricted. It would cause exhaust back pressure to make the car misfire at 5k but behave normally under 5k. Also failed to mention above... when this happes the check engine light is flashing and continues to flash for about 20 or 30 seconds after backing off the throttle. As if it takes that long for all that exhaust to pass the cat. You should also know I ran with p1312 and p1334 codes for a year due to lack of money for car parts. Wasn't until it driving like crap one day that the dic was needed.
 

·
Registered
Joined
·
2,284 Posts
Well, I'm sure you know, flashing CEL means random misfire and is 99.9% the DIC. When my cat was plugged, the exhaust shop told me I was lucky that it plugged rich and not lean. If yours is actually plugged, my guess is from a lean condition which can cause massive spikes in internal temperature and melt pistons. As I said, when mine plugged, I could barely make it up a hill no matter how hard I pressed the go pedal. It all came back to my DIC which wasn't firing properly and caused the cat to fry. I hear you though, it's a new DIC, but it doesn't mean the quality control inspection was done on that unit. I work in Automotive parts Manufacturing and these things happen, whether it was a robotic welder that went out of spec, or a disgruntled employee who just didn't follow the work instructions at their cell, who knows. I hope you get it sorted sooner than later though. I cheaped out and it ended up costing me triple by the time everything was said and done.
 

·
Registered
Joined
·
344 Posts
Discussion Starter #8
Well, I'm sure you know, flashing CEL means random misfire and is 99.9% the DIC. When my cat was plugged, the exhaust shop told me I was lucky that it plugged rich and not lean. If yours is actually plugged, my guess is from a lean condition which can cause massive spikes in internal temperature and melt pistons. As I said, when mine plugged, I could barely make it up a hill no matter how hard I pressed the go pedal. It all came back to my DIC which wasn't firing properly and caused the cat to fry. I hear you though, it's a new DIC, but it doesn't mean the quality control inspection was done on that unit. I work in Automotive parts Manufacturing and these things happen, whether it was a robotic welder that went out of spec, or a disgruntled employee who just didn't follow the work instructions at their cell, who knows. I hope you get it sorted sooner than later though. I cheaped out and it ended up costing me triple by the time everything was said and done.
Actually a flashin cell means catalysts damaging missfire. And I can give you a set of spark plugs and a set of injectors that can cause the same code and symptom. And what about the 3 used sem dic's that I tested and the car ran the same? Thats why I think it could be the fuel pump as well, or maybe the fuel pressure regulator. If I dont get fuel enough fuel to meet the demand. And as far as what I am suggesting happened to my cat... imagine if I packed my cat full of carbon, till it was 100% restricted... then drill a 3 inch hole in it with a hole saw. Its possible to melt that way, just probally less probable.

And then theres this guy.

Haven't read to his end but plan on it just to check his solution.
 

·
Registered
Joined
·
87 Posts
To diagnose a fuel pump, simply go WOT and check your upstream O2 voltage... it should go rich (~0.8v) at WOT until you let off. A failing fuel pump will not allow you to maintain the rich condition. As for a plugged cat, restricting the air OUT of the engine would restrict the amount of air able to come INTO the engine. This would likely be seen as a drop in MAF readings compared to a normally running vehicle at a particular rpm; 5k for example. I don't know anything about what the cat should look like on the inside, but using basic knowledge the tests above can be used to point you in the right direction, or confirm your findings.

Side note... ProParts DI's are T-R-A-S-H. As a former employee of eEuroparts, they pushed those pieces of crap HARD because of the profit margin. We bought them cheap and sold them very high. The failure rate of them is unbelievable. Failing in the first 3 or 4 months is far from unheard of. That's why we all recommend SEM or a good used one.
 

·
Registered
Joined
·
344 Posts
Discussion Starter #11
To diagnose a fuel pump, simply go WOT and check your upstream O2 voltage... it should go rich (~0.8v) at WOT until you let off. A failing fuel pump will not allow you to maintain the rich condition. As for a plugged cat, restricting the air OUT of the engine would restrict the amount of air able to come INTO the engine. This would likely be seen as a drop in MAF readings compared to a normally running vehicle at a particular rpm; 5k for example. I don't know anything about what the cat should look like on the inside, but using basic knowledge the tests above can be used to point you in the right direction, or confirm your findings.

Side note... ProParts DI's are T-R-A-S-H. As a former employee of eEuroparts, they pushed those pieces of crap HARD because of the profit margin. We bought them cheap and sold them very high. The failure rate of them is unbelievable. Failing in the first 3 or 4 months is far from unheard of. That's why we all recommend SEM or a good used one.

First off I said I solved the mystery and rulled it to be a bad cat. Also regardless of if your wot or not, your upstream o2 should not go .8mv (rich) the sensor needs to be switching rich/lean or your cat doesn't function properly. Secondly if wot casues a p1300 aka p0300 at 5k rmp (wot) that test wouldn't be valid because with multiple random missfires the o2, fuel trims, mass air flow is all gonna be outta wack. The correct test would be to do a fuel flow test where you drop the tank power up the fuel pump and find out how many gallons per second your flowing and compare to specs.

Also for clarification I attached 2 more pics. One which is what a cat should look like the other is my cat which is broken with notes written on the picture.

Also I have had pps and sem dics torn apart and have seen that they look completely different, on the other hand... the pps that I pulled out of the car worked for 4 years, after the 5th year threw the p1312 code, about 6 months later got the p1334. In 6 more months, it started miss firing bad enough that I was forced to change it. Although, when I can afford it, I keep my car in proper working order all the time, some people be driving around on blowen head gaskets till the car stops. My whole problem with throwing a dic at it is there are no codes that simply lead to a bad dic. P0300 and p1300 is caused by air flow, fuel, spark, exhaust flow, even the coolant temp sensor can generate that code. I have also saw a lexus a customer changed his own oil on. This car had a p0300 and found that the dude must have used 3 gallons of oil cause when you pull the dipstick you can litterly see the oil in the dipsick tube. I am frankly shocked he didnt end up with a hydrolocked engine. And had I listened to everyone screaming bad dic, I would have spent $250 on a new dic, but would have had to turn around and spend another $1200 on a catalytic converter.
To diagnose a fuel pump, simply go WOT and check your upstream O2 voltage... it should go rich (~0.8v) at WOT until you let off. A failing fuel pump will not allow you to maintain the rich condition. As for a plugged cat, restricting the air OUT of the engine would restrict the amount of air able to come INTO the engine. This would likely be seen as a drop in MAF readings compared to a normally running vehicle at a particular rpm; 5k for example. I don't know anything about what the cat should look like on the inside, but using basic knowledge the tests above can be used to point you in the right direction, or confirm your findings.

Side note... ProParts DI's are T-R-A-S-H. As a former employee of eEuroparts, they pushed those pieces of crap HARD because of the profit margin. We bought them cheap and sold them very high. The failure rate of them is unbelievable. Failing in the first 3 or 4 months is far from unheard of. That's why we all recommend SEM or a good used one.
To diagnose a fuel pump, simply go WOT and check your upstream O2 voltage... it should go rich (~0.8v) at WOT until you let off. A failing fuel pump will not allow you to maintain the rich condition. As for a plugged cat, restricting the air OUT of the engine would restrict the amount of air able to come INTO the engine. This would likely be seen as a drop in MAF readings compared to a normally running vehicle at a particular rpm; 5k for example. I don't know anything about what the cat should look like on the inside, but using basic knowledge the tests above can be used to point you in the right direction, or confirm your findings.

Side note... ProParts DI's are T-R-A-S-H. As a former employee of eEuroparts, they pushed those pieces of crap HARD because of the profit margin. We bought them cheap and sold them very high. The failure rate of them is unbelievable. Failing in the first 3 or 4 months is far from unheard of. That's why we all recommend SEM or a good used one.
 

Attachments

·
Registered
Joined
·
87 Posts
First off I said I solved the mystery and rulled it to be a bad cat. Also regardless of if your wot or not, your upstream o2 should not go .8mv (rich) the sensor needs to be switching rich/lean or your cat doesn't function properly. Secondly if wot casues a p1300 aka p0300 at 5k rmp (wot) that test wouldn't be valid because with multiple random missfires the o2, fuel trims, mass air flow is all gonna be outta wack. The correct test would be to do a fuel flow test where you drop the tank power up the fuel pump and find out how many gallons per second your flowing and compare to specs.

Also for clarification I attached 2 more pics. One which is what a cat should look like the other is my cat which is broken with notes written on the picture.

Also I have had pps and sem dics torn apart and have seen that they look completely different, on the other hand... the pps that I pulled out of the car worked for 4 years, after the 5th year threw the p1312 code, about 6 months later got the p1334. In 6 more months, it started miss firing bad enough that I was forced to change it. Although, when I can afford it, I keep my car in proper working order all the time, some people be driving around on blowen head gaskets till the car stops. My whole problem with throwing a dic at it is there are no codes that simply lead to a bad dic. P0300 and p1300 is caused by air flow, fuel, spark, exhaust flow, even the coolant temp sensor can generate that code. I have also saw a lexus a customer changed his own oil on. This car had a p0300 and found that the dude must have used 3 gallons of oil cause when you pull the dipstick you can litterly see the oil in the dipsick tube. I am frankly shocked he didnt end up with a hydrolocked engine. And had I listened to everyone screaming bad dic, I would have spent $250 on a new dic, but would have had to turn around and spend another $1200 on a catalytic converter.
Hey thanks for the reply. I didn't actually read it. I should have realized by your previous responses that you're an incredibly condescending child who posts "problems" in order to show the world you're so much "smarter" than our offered logic... Yet you still post question on the forum seeking advice.I won't be checking your responses from here. Best of luck with your broken car!
 

·
Registered
Joined
·
344 Posts
Discussion Starter #13
Hey thanks for the reply. I didn't actually read it. I should have realized by your previous responses that you're an incredibly condescending child who posts "problems" in order to show the world you're so much "smarter" than our offered logic... Yet you still post question on the forum seeking advice.I won't be checking your responses from here. Best of luck with your broken car!
Well thats the funny thing, apparently you still have yet to learn how to read since I have said teice now that I solved this problem. And sorry for not accepting a less throw some parts at this to fix it... just like everyone else that changed dic, plugs, injectors, motor swaps and god knows what else... and 3 times each. Show me a logical reason to swap my dic and I'll entertain the idea. And its not that I am condescending... I guess I expect to much of people... just read the headline people... then respond appropriately like the hero, ignoring what everyo e else says or any of the key symptoms.
 
1 - 13 of 13 Posts
Top