No Power...rough Idle & Loud Exhaust Spuddering

[curiousB]

From your description ...........would throw a code.....

There are ........for your help.

I'd do a search of this forum on wiring of distributor cap. I don't recall if it is the high voltage wires arcing to the engine block or the primary wires on the coil (shorting to frame due to pinched wire) but I have read a few posts about this. Those would be other things to check in addition to the cap as you noted.

[Quack11]

From your description ...........would throw a code.....

There are ........for your help.

I'd do a search of this forum on wiring of distributor cap. I don't recall if it is the high voltage wires arcing to the engine block or the primary wires on the coil (shorting to frame due to pinched wire) but I have read a few posts about this. Those would be other things to check in addition to the cap as you noted.

Thanks "CuriousB", i'll be doing a full inspection of the distributor and CPS as soon as I get back on that coast. I've bought an OBD I&II code reader to further assist with any codes that may not have been displayed and I hope to find and fix this problem. Will post the findings when complete.

[lisach]

sorry to jump in here but I would like to hear your experienced opinions on my situation. Let me preface by saying that I'm not a mechanic (but very technical) and would graciously bow to the vast experience congregating here.

I am having similar problem with my 91 LS400. The car was parked for a couple of years with monthly start-ups and round the block runs to give it "semi" workouts. Then it got a good 300 mile run about 2 months ago. During the trip it would act like it was running out of gas and just quit. Pull over and after a few minutes it would start and go. This happened dozen or so times during the 4 day trip.

After returning and sitting a couple of weeks, when it was started up again it wouldn't hardly make it out of the driveway. It has been that way ever since. So when started, it acts like it is going to run out of gas but will stay started and run at idle. Attempts to drive round the block result in barley topping 15 MPH. After warming up it seems to run a little better. When the RPM is raised to about 2500 the roughness seems to level out. check engine light is on. Carried it over to have analyzer Hooked up and it gave the codes of 24 Idle Air Temp sensor (understandable...a hose was leaking giving a vacuum leak) and 41 Throttle Position Sensor (moderately $$)

I have read all of your replies to this topic and am wondering the following:

I have decided to part this car out. There is nothing wrong with it (just needs some basic TLC) but the value seems to be 2-3K and everyone who has responded is looking for a 2-3K car and therefore it is not the car for them. I am sure you understand what I mean. 18 years old etc....

I am certain the problem is not mechanical but electrical/sensor.

In parting it out, obviously I can't sell the engine saying, "hey I think it's good but...."

With your experience in these matters how would you deal with this?

1) sell as is...hoping to get someone who will accept it with those circumstances? I MEAN HOW DETRIMENTAL IS THIS PROBLEM TO THE OVERALL ENGINE AFTER COMING OUT AND GOING TO SOMEONE ELSE?

2) spend money and time....replace sensors...and hope that fixes the code...only to sell the parts?

3) spend money and time...replace sensors....and continue to T-shoot issues as they arise (very possible) only to invest more money and time in something that is going to come apart?

4) Is there kind of way to sort of.... fool it....to see if that's really the only problem?

Please be kind in your replies to what may seem like stupid questions. LOL

And oh yeah...could anyone point me to a parts list?

Regards and Blessings,

Lisa

[Quack11]

Ok, so I am finally back on the East coast and jumped right into fixing this problem. I purchased an OBD I&II scanner and hooked it up to the diagnostics port and it gave me a code 31 (MAF sensor). Took the sensor off and did some more cleaning and even open it to see the setup, too complicated for me so I re-assembled and installed only to find the same problem. I've now noticed that the car in burning rich (light blue smoke and that rich smell of gasoline) Tried to drive it and got the same problem so I will be on the market for a new MAF sensor and see if the problem goes away. I changed the IACV also since I had an extra one sitting around. I'll post the final results when I get and install the MAF sensor. Thanks for all your help.

[RandySC400]

OK MY CAR IS UP AND RUNNING AGAIN...IT WAS MY DRIVERS SIDE COIL THAT WENT BAD!I WOULD LIKE TO FLY TO JAPAN AND PUT MY FOOT UP THE DESIGNERS !Removed! WHO DESIDED TO PUT THE COIL IN SUCH A STUPID SPOT!!! ANYWAY GUYS THANK YOU THANK YOU AND THANK YOU FOR ALL OF YOUR SUGGESTIONS AND ADVICE!!! MY BABY IS BACK ON THE ROAD!!!! YEAH!!

AS FOR "LISACH" WHOSE POST IS JUST ABOVE MINE... CHECK YOUR TPS I BOUGHT MY LS FOR 250.00 AND IT WAS DOING THE SAME THING YOURS IS DOING..THERE ARE 2 SCREWS YOU CAN LOOSEN AND TURN IT TO ADJUST YOUR THROTTLE....AND YOU CAN CLEAN YOUR MAF TOO.... TRY TO ADJUST YOUR TPS BEFORE BUYING ONE

THANKS AGAIN GUYS!!!

[Quack11]

There goes another happy ending to a LS problem. Randy sure seem happy and it's because of everyone's effort. This forum is a great place.

[Quack11]

There goes another happy ending to a LS problem. Randy sure seem happy and it's because of everyone's effort. This forum is a great place.

Forum, I got a MAF sensor and installed it on my car, check for codes and start it up. The car is back to normal and is driving just fine. Thanks for all the assistance and I am very excited to have it back on the road.

[playaike]

thanks guys im going to do the MAF and check the coils...i gave the car a full tune up like 5 or 6 months ago...thats why i was so surprized when my plugs were totally shot...also my car is just not rough at idle but also when its in drive...i can barely get over 10 mph! it running so bad!...Would a TPS through a code or would a bad TPS be the cause??? i had simular problems with my SC400 and my cats were glowing red!...thats been parked and another whole project i have!! anyway thanks for the advice and i will let you all know how it goes...hopefully it will be a quick easy and inexpensive fix! thanks again

hey! wat was the problem wit ur sc400 when your cats were glowing red hot im have the same problem wit ls400 including a loss of power

[landar]

This be an old thread and the OP's are likely long gone. Glowing red cats are usually caused by one or both coils going bad. I suppose a bad main wire feed(coil to distributor) or badly damaged rotor could do the same thing but most likely it is the coil(s). The extra hot cats are a result of unspent fuel in the combustion chamber due to lack of proper ignition.