Contour Enthusiasts Group Archives Forums General Troubleshooting lost power, dimming lights...read on...

i know i've been at this before, but i'm here again.. with the same problem, at least i think so. If you read my previous post a few months ago, i had my IMRC and various other components except the cat changed at the dealer.

Here's the deal: shes bogging down on hard acceleration.. again. i had the imrc, IAC and an o2 sensor changed in october to solve it then. seemed to have worked.

i recnetly overheated severly due to my waterpump going sour, could i have fried the new IMRC? i did drive for 20 minutes on overheat

i've always had a poor fuel economy issue since i bought her . so i followed the directions and advice from my fuel ecomomy post

made a big difference... the car was running great.. so i drove hard.. blew the tranny 2 days later replaced under warranty

my CEL came on , local guys pulled "catalyst below efficiency bank 1" ... they cleared it, it came back.. stayed for 2 weeks.. now went away on its own!

at current when i accelerate hard, i notice my dash lights dim down... aside from the lack in power.. and i swear to god she sounds different too.. but that might be in my head.

I know this is gonna involve alot of reading, but can someone please help me!

ok. i see most have given up on me since the majority of answers are in my other post...

i guess plain and simple:
1) why do my lights dim on acceleration?
2) can a new IMRC be cooked due to a severe overheat?
3) Do i bite the bullet and change the cats.. or could it be anything else?

thats the distilled version of my post, the rest is just alot of venting!

BUMP

Severe overheating can, and is known to warp the heads in these cars. On the other hand if it is idling smooth and isn't overheating then you may have gotten lucky and didn't damage the head. Sounds like you may have a bad alternator or voltage regulator. If your voltage drops significantly then it will affect the engine management system. Check the voltage output of the alternator. You can do this without removing it or have it done for you. Most auto parts stores will do this for free. Checkit at idle and at various rpm's.

Your precats are probably nearing the end of their life. They're warranted for 8 years/80,000 miles. When mine started failing, the CEL would come on for a couple of days, then go off for a couple of weeks. Eventually, it stayed on full time. Since I had 100,000 miles at that time, the warranty wouldn't cover replacement of the precats, and the dealer recommended just leaving them alone if the car still ran OK. So my CEL has been on for the last 65,000 miles, and will probably stay on until the car hits the junkyard.

seeing how my car is a 98... i think i just went over the 8 year limit. i only have 107000KM (66500 miles)

the dealer screwed me, i asked them to check it back in october, cause i could get the rotten egg smell, but the CEL didnt give them the right codes then... and my light is off now... would the code still be in memory?

another bit of info to add... when my heater is on, it changes speed with my rpm range, the faster i drive or more i rev: the louder/faster my blower is.
and.. i noticed that my car has been hunting for idle speed at startup.

i attached my voltmeter to the battery post while the car is off, and i got 12.65 volts, once started i got around 14.75, with minor fluctuations. i increased the load by putin every accessory on. not to much difference... i even put my system on, cause i know that causes dimming, just to test. on low base notes i'd drop to 13.## and jump back up. i reved by hand, and noticed that at one point it spiked to 15.## volts

now the oddest thing was when i reved very lightly with most of my accesories OFF, except maybe the heater, there was a momentary loss in voltage right down to 12 volts... and i could actually hear the loss.. then it spiked back to 14.. and i could repeat this by reving very light aprox a quick tap to 1500 - 2000 rpm

Is that normal? or do i need a new voltage regulator/ alternator/ both?

PS: now keep in mind i couldnt see my tach, so it may be possible that my rpm droped lower than 750 when i lost voltage.

ummm... bump