nonamedude

I think i have a bad sensor or ECU or something but im not sure how to tell. I am kinda bad with cars. I got in a wreck and got it fixed and having all sorts of problems now that i didnt have before. Fixing it was all body work and replacing the radiator.

After I got it put back together we were having the surging idle problem with the TPS but we didnt replace it. the guy at the body shop said he "glitched" it. while it was running he loosened it and plugged it back in and the problem stopped.

My new problem, and i dont know if theyre related, is that the car idles around 300 rpms and when i turn on the A/C the rpms drop so much so that i have had the car stall because of it. It is my understanding that the rpms should go up to compensate for the added strain on the engine when you turn on the A/C. Also if the A/C is on when i accelerate i can feel it bogging down alot and i can notice a major difference in power if i turn the A/C off. I dont know whats causing the problem but from looking around i have the ideas of TPS, IACV, and vacuum leak. I dont know how to check for vacuum leaks. I have read some stuff but dont really understand it.

I have a 99 lx 5 spd. It has never given me any troubles before this. Thanks for the help.

Former User

Is the A/C compressor or idler pulley noisy when the A/C is ON? Just wondering whether the strain on the engine may be due to the A/C moving components binding up.

Is the engine having any other running/idling problems? Is the CEL ON? If so, what code(s) is being thrown?

Alternatively, try cleaning the IACV on the throttle body and adjusting the idle screw on the throttle body. There is a circuit that ramps the idle speed up when the A/C is ON, but start with the basics first.

nonamedude

well there is this horrible high pitched squeal at about 3500 rpm that i hadnt noticed because i hadnt revved it with the a/c on. Also the a/c works fine its just the problems that come along with it.

there was a CEL when the TPS was giving a fit. P0505 which is like throttle ignition problem or something. but there isnt one anymore.

which sensor is the IACV? its the other one on the throttle body that isnt the TPS right? use carb cleaner? i no there is a guide somewhere so i will have to find it and do that when i get a chance. prob tomorrow.

Former User

Check whether the squeal is coming from the idler puller for the A/C belt (highest pulley). It may be seizing up and causing the problem. P0505 could indicate a faulty IACV. It's attached to the throttle body, connected to two small coolant hoses and an electrical connector. Yeah, clean it with carb cleaner.

nonamedude

Well the squeal is coming from the front right of the car where all the belts and stuff are. around the a/c compresser is what my dad said. he said he thinks the compressor may be going out but he wasnt sure.

Former User

Yep, a bad compressor could be causing your idle problem.

blk_eg4

ok before you start suspecting your compressor is causing it..first adjust the a/c belt and make sure its tight, i had a problem like this before where it would squeal when a/c was on so i adjusted the belt and it went away..next is the idling problem, first check to see if the pressure switch on the condenser is working properly, i had a similar problem before where the a/c was causing really low idle to the point of stalling, i had it checked and it was due to a bad pressure switch on the condenser..

nonamedude

well the belts or belt (i dont know if its more than one) all seem tight. and i dont have a clue where the compressor switch would be (other than on the compressor) or how to check it.