- Thread starter
- #21
OK, will do thanks again! I love this forum, everyone is so knowledgeable!
98 LC. Son was driving it to school today said about halfway there is started running rough...
- Thread starter COLandCrusher
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I've had some of these issues in the past. I replaced the coil packs in the cylinders that were throwing the codes, but she still didn't run right. I decided to pony up the cash and replace them all, and then she ran like a champ!
I might be wrong, but I thought electronic throttle control wasn't available until 03'. If yours is a 98' it should be drive by cable.
I might be wrong, but I thought electronic throttle control wasn't available until 03'. If yours is a 98' it should be drive by cable.
I thought all 100s used a TPS and electronic throttle. At least that's the way it appeared in my '00.
It has TPS and electronic throttle but it isn't fly by wire, it still has a cable going to the TPS which is mounted on the throttle body.
- Thread starter
- #25
well there is a cable there. I am not sure how to adjust it though. Do you all still think cleaning the MAF sensor would help? I do not believe it has ever been done- about 9 years now.
I just looked it up in the fsm, and this is correct. 98'-02' has an electronic throttle motor, but is drive by cable. 03' and up is drive by wire. Always thought drive by cable meant no throttle motor. Took the engine cover off and you can't miss the motor.
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You should not have to adjust cable. It was working before this issues so leave it alone. Something else, possible vacuum leak or just in need of tune up. Removing the intake air box, it's common to forget some vacuum lines. Also common is not re connecting MAF properly.
You were unclear on code you got while/when parts guy plugged in. What codes did he get?
Very often coils go bad due to bad spark plug having wide gap (do not re-gap used plugs just replace) they draw to much power from coil overheating. So rule of thumb check plugs when replacing coils. When to replace Ignition coils.
- Thread starter
- #28
the codes were p 0300 (multiple misfire) and a 0302 which was cyl 2 misfire. I replaced cyl 2 coil. the other code was from when I had to have key reprogrammed. (immobilizer code)
About a year ago I did my own spark plugs on it, I replaced the iridium plugs with standard plugs. I am thinking maybe I should have went with the Iridium ones again. Didn't really make any difference at the time tho in how it drove and ran.
About a year ago I did my own spark plugs on it, I replaced the iridium plugs with standard plugs. I am thinking maybe I should have went with the Iridium ones again. Didn't really make any difference at the time tho in how it drove and ran.
Go buy Denso plugs, that is what came in the truck.
The 2UZ-fe doesn't take "regular plugs" they will not last and will burn up coils$$$$$$$$$.
Normally you'd swap coils to see if code moves where swapped to. Did CEL reappear?
Sound like it's running worst now, so indication you did something wrong.
They way you describe it barely running, is like when I start engine with intake air box off the car. So I'll repeat; check MAF connection & all vacuum lines. Make sure intake air tube is properly fasten to T-body & air filter box.
- Thread starter
- #32
Ok so I should better clarify. The engine is running perfectly smooth, much better after replacing #2 coil. So that fixed my issue. The issue now is that it wont hold at a higher idle. Even though it's perfectly smooth it's just very low. was about 400RPM. but after driving and hitting brakes, it would sometimes go down to 2-300. Should I bother cleaning the MAF sensor with electrical cleaner? I'll check the connections tonight. Son gets home from work at 8PM.
I'd use MAF cleaner only (not electrical parts cleaner), just to be safe.
So I'll repeat; check MAF connection & all vacuum lines. Make sure intake air tube is properly fasten to T-body & air filter box. Use a good light so you don't miss anything.
I'll add to above list: Also make sure air filter is clean. Also clean Throttle body throat and PCV. If you find a bad vacuum hose, tape tight the best you can with electrical tape, until you can get new hoses this week or next week.
Note: Make sure you start by disconnecting battery, and clean and re grease battery post. Don't connect battery until done with everything else, or at minimum 30 minutes to reset ECM.
So I'll repeat; check MAF connection & all vacuum lines. Make sure intake air tube is properly fasten to T-body & air filter box. Use a good light so you don't miss anything.
I'll add to above list: Also make sure air filter is clean. Also clean Throttle body throat and PCV. If you find a bad vacuum hose, tape tight the best you can with electrical tape, until you can get new hoses this week or next week.
Note: Make sure you start by disconnecting battery, and clean and re grease battery post. Don't connect battery until done with everything else, or at minimum 30 minutes to reset ECM.
- Thread starter
- #34
OK got it. Thanks so much! i'll keep you all posted.
- Thread starter
- #35
So i noticed the bottom of the airflow unit was cracked. I repaired with gorilla tape, cleaned the sensor with MAF cleaner, and after reconnecting battery it started and idled better than it has for some time. About 550 rpms. Very quiet and perfectly smooth. Even seems to have a bit more power/acceleration!
Congrats you found the problem!
Remember to disconnect battery first thing and re connect last thing when doing tune-ups, it reset ECM. Your ECM (engine control module) which is just another way to say ECU (engine control unit). Which controls your air / fuel ratio and spark timing. Disconnecting for 30 minutes is so it can relearn (reset). It will take some driving time to adjust to engine conditions, altitude, fuel grade & driving style.
You'll need to replace spark plug ASAP with factory recommend ones. Always use factory recommend parts in the 100 series, it pays.
Tips:
Bake soda neutralizes acid. I like to start each annual tune up by cleaning battery by generously sprinkling baking soda on battery. Then sprinkle with water. Keep adding baking soda as long a blue appear when water added. Always clean & grease battery post, to keep from oxidizing.
PCV valve get plug and need cleaning. The grommet it fits into on DS valve cover gets loose and needs replacing. The hoses (one PCV hose on each side) crack at ends and need replacing. After cleaning PCV with solvent, water and high pressure air test it. Air should pass in one direction and not the other.
Vacuum hoses that crack at ends become loose need replacing.
You'll need to replace spark plug ASAP with factory recommend ones. Always use factory recommend parts in the 100 series, it pays.
Tips:
Bake soda neutralizes acid. I like to start each annual tune up by cleaning battery by generously sprinkling baking soda on battery. Then sprinkle with water. Keep adding baking soda as long a blue appear when water added. Always clean & grease battery post, to keep from oxidizing.
PCV valve get plug and need cleaning. The grommet it fits into on DS valve cover gets loose and needs replacing. The hoses (one PCV hose on each side) crack at ends and need replacing. After cleaning PCV with solvent, water and high pressure air test it. Air should pass in one direction and not the other.
Vacuum hoses that crack at ends become loose need replacing.