NewGuy19 Posted November 28, 2007 Share Posted November 28, 2007 Ok here it goes. I'm trying to figure out as many problems as I can with my car that way I can fix them over my break in a couple weeks. I already plan on fixing the antena and replacing the sub in the car. As well as do a brake job. I have a couple questions about a few other things though. When I bought this car the mechanic told me there was a vaccume line broken somewhere which caused the cars rpm's to surge while in park or neutral. However I have not found any bad lines as of yet. The car typically won't start surging right away when you start it up. The rpm's slowly climb to around 2000 and then it starts surging, usually going between 700 and 1800 rpm's. I did a little searching of my own and noticed that when I unpluged the mass air flow sensor the car stopped surging and simply idled around 1800 rpm's. Do you think the MAF is the cause of this problem? I also noticed about a week ago, that when I'm accelerating with the car the parking brake light comes on. It will stay on while accelerating then typically shuts off when you let up on the gas and are either slowing down or maintaining a constant speed. I have pulled the lever in the car several times to release it and make sure the brake isn't patially engaged, but have not done much other checking since it's fricken cold outside now and I don't have a garage to put it in at the moment. Quote Link to comment Share on other sites More sharing options...
NewGuy19 Posted November 30, 2007 Author Share Posted November 30, 2007 Doesn't anyone have some help here? Quote Link to comment Share on other sites More sharing options...
Sanpete Posted November 30, 2007 Share Posted November 30, 2007 It could be your MAF sensor, but not necessarily. As I understand it, when you disconnect it your computer will essentially override some other sensors too, hiding all kinds of potential causes. If the part is old anyway, it wouldn't hurt to start by replacing it and see if it fixes the problem. They do fail eventually. You can get it cheaper online (search here or at google for parts suppliers). But if no one here can give more definite advice, I'd call a local Lexus or Toyota dealer and ask what the most likely cause is--they're often quite helpful, when they want to be. Check your rear wheels after the parking brake light has been on and see if one of them is hotter than the other, which would indicate sticking on that wheel. If not, it might be that you have a loose or frayed wire somewhere. A common problem for your year LS is fraying of the wires that pass along the trunk hinge--you can inspect them easily. I haven't heard of this particular problem coming from that source, though. Otherwise I'd suspect the wiring up front or the parking brake release sensor, which I know nothing about. Hopefully someone with more experience with 1st gens will chime in soon, but it can sometimes take a little while. Good luck. (You could also ask at clublexus while you're waiting.) Quote Link to comment Share on other sites More sharing options...
NewGuy19 Posted December 4, 2007 Author Share Posted December 4, 2007 Hey all, I've been doing a lot of searching through this site, as well as others trying to gain as much knowledge about these problems as I can. I've found several posts where people identify the same surging while in park and neutral. However none of those posters have the same rpm swing I do. I've read that the IAC valve and the air control valve are both good places to look at as well (please correct me if I'm wrong). I still am looking for imput on this problem though. I also borrowed a friends laser thermometer, and ran a few tests on my brakes. I took my car out driving a few different times, then quickly crawled under the car and took a reading of the temp's of each brake area. I know that's not the correct way to do things. But right now it's all I can do till I get home to my tools. I noticed that the passenger front tire was always warmer than the other tires by about 50-70 degrees. I'm not sure if that's related to my parking brake light coming on though. Any help would be greatly appreciated. Quote Link to comment Share on other sites More sharing options...
Sanpete Posted December 5, 2007 Share Posted December 5, 2007 The higher temp for your front wheel does mean something (it's doing more braking than the other wheels), but it may not be related to your other troubles. You'll want to check the brakes on that wheel, though. When you say that the others don't report the same rpm swing, do you mean they have rpm swings but of different amounts? (Because surging in neutral is rpm swings.) Do check the wiring along the trunk hinge for the parking brake light problem. Quote Link to comment Share on other sites More sharing options...
bobls400 Posted December 6, 2007 Share Posted December 6, 2007 i had the same brake light coming on. it was just low brake fluid, i added some and the light went out. Mine was coming on at the same times, i assume that the fluid was moving around when accelerating. Quote Link to comment Share on other sites More sharing options...
glenmore Posted December 6, 2007 Share Posted December 6, 2007 Regarding your parking brake light. This idiot light refers to two things, your parking brake and brake fluid level. Make sure your brake fluid is at the correct level. If it is and the park brake light stays on even after you release the parking brake, it may be a precursor to your alternator failing. With anything hinky with your idiot lights, check the fault first and if there is no fault (i.e. low fluid level) check the alternator. My alternator failed about 150m. Before that the park brake light would dim a little after I released it but would remain faintly lit. Later all the idiot lights went on while my son was driving and the batterey completely drained resulting in no start the next morning. A new battery cured some of the idiot lights but the battery charging light was still lit. That's when I checked the forums and narrowed it to the alternator. 1990 LS400 1991 300CE 2000 C280 Quote Link to comment Share on other sites More sharing options...
NewGuy19 Posted December 8, 2007 Author Share Posted December 8, 2007 Well I went out to start my car today and my battery was completly dead. I got a jump from a friend and let my car run for about 15-20 minutes to hopefully charge the battery up. After that I shut the car off and when I tried to restart it the battery was completly dead again. While the car was running the parking brake light stayed on the whole time. I'm assuming the jump was enough power to get the starter cranking as it should have done, then after that all my power from comming from my alternator, and my battery is shot. If any of you agree with this thinking, or have any other ideas please let me know. I plan on pulling the battery later tonight after the snow lets up and I'll get get a new one tomorrow. Again any help would be greatly appreciated. Quote Link to comment Share on other sites More sharing options...
Sanpete Posted December 8, 2007 Share Posted December 8, 2007 Could still be the alternator. If you let the car idle for 20 minutes, that probably didn't charge your battery much, especially if the alternator isn't working as well as it should. Quote Link to comment Share on other sites More sharing options...
glenmore Posted December 9, 2007 Share Posted December 9, 2007 Well I went out to start my car today and my battery was completly dead. I got a jump from a friend and let my car run for about 15-20 minutes to hopefully charge the battery up. After that I shut the car off and when I tried to restart it the battery was completly dead again. While the car was running the parking brake light stayed on the whole time. I'm assuming the jump was enough power to get the starter cranking as it should have done, then after that all my power from comming from my alternator, and my battery is shot. If any of you agree with this thinking, or have any other ideas please let me know. I plan on pulling the battery later tonight after the snow lets up and I'll get get a new one tomorrow. Again any help would be greatly appreciated. Was the battery charging fault light on while you were idling? Rebuilt alternator is not too $$. There is an ebay seller from Southern California that is inexpensive. IIRC it was like $50 with your core. The repair itself is simple, the only time consuming part is juggling the new one into position. Don't drain your brand new battery without checking your alternator! Most places selling batteries (like Sears) will check your charging system for free. glenmore 1990 LS400 1991 300CE 2000 C280 Quote Link to comment Share on other sites More sharing options...
cardona6569 Posted December 9, 2007 Share Posted December 9, 2007 Hello: It looks like your battery and alternator are bad, I would replace both, but first before spending money I would recharge the battery then, take it to a place where they check the system and see if the alternator is gone, which I am pretty sure it is. The Maf Sensor thing... if you look in the forums of the UK they're ways of cleaning the Maf and there are other ways to electrically test the part. I would clean it first, and put a nww air filter. See what happens if not effect open that engine and chase all of those vacum lines, clean all connectors you can get to with electronic parts cleaner, if no avail, clean the Thortle body also the Idle Control Valve, if none of these DIY do not fix the problem, then you will need a professional, because is beyond the normal maintenance done by the non-auto mechanics. Let us know what you find and what it took to get it fixed. CPR CPR Quote Link to comment Share on other sites More sharing options...
NewGuy19 Posted December 9, 2007 Author Share Posted December 9, 2007 Hey, I have a little update for you all. I pulled my battery to go get that tested today and it turned out the battery was shot, which I kind of suspected. It turns out the dealer just threw a cheap underpowered battery in there to sell the car. Kinda ticks me off being I questioned him when I bought the car a few months ago, and he told me it was the proper battery for the car. I don't have time to take the car back down to get the alternator checked today as I have 3 finals tomorrow and I have not had time to study yet. But plan on taking it down after that. As far as the MAF I cleaned it a couple months ago trying to fix the problem to no avail, I also changed the air filter and cleaned the throtle body at that time. I guess while I'm home and have nothing to do I can take cardona's advice and start following lines and cleaning connections. I'll let you all know what I find out about the alternator tomorrow, and will probably have many more questions for you. Thanks to everyone who's helped so far. Quote Link to comment Share on other sites More sharing options...
NewGuy19 Posted December 10, 2007 Author Share Posted December 10, 2007 I took the car to an autoparts store this afternoon and they tested the alternator and told me it was just fine. That's a big relief being I'm heading home on Thursday. However, the brake light is still lit up. I checked the brake fluid as some of you mentioned and it's at the proper levle. It snowed last night and I noticed that with the new snow on the ground the front tires lock up when you reach real slow speeds. Typically just before I come to a stop they lock up and just slide. It doesn't matter what I tried doing I still had the same outcome. When I try pumping the brakes gently like you would in a car without anti-lock I get a bad grinding feeling in the brake pedal. Anyone have any input on this new problem? Sorry for all the questions in the last week, things just seem to all go out at the same time with me it seems. And believe it or not I can fix a lot of things on a car when I have my tools (probably doesn't sound that way), however I am terrible at identifying what's wrong. Quote Link to comment Share on other sites More sharing options...
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