Beretta.net

I just drove the car for over 1500 miles without a problem. I went out today to drive it and it started acting up. the first thing it does when cranked is the rpms go way up high to like 5,000 and it doesn't come down from there. I removed the hose from the map and the rpms when down to 1,000 but still runs like crap. There were also what sounded like noises coming from the exhaust or the cat not really sure. If you connected the hose back up to the map sensor then rpms go high again. Can the computer be bad mayber? i tried another map sensor i had and no change at all. Also while trying to the find the problem i disconnected the sensor that goes on the air filter box and it started acting like crazy. What do you guys think? i know my problem is not fuel related but rather electrical.  thanks guys!

If you get under the car and bang on the cat does it make noise? The computer will try to keep the car running at any cost. My ignition switch went out one time and I pulled all three plug wires on the front to kill it, the computer kept the engine alive. The sensor in the air box is the inlet air temperature. It tells the computer the air temp and barometric pressure(your's sounds like it's ok, just keep it hooked up).

well, what else could it be besides the cat and the computer? i've had this car for along time and i have never had any problems like this one. Any ideas? i will check the cat tomorrow and get back to you on it. thanks

Test and clean the IAC and the passages.

i have already done that before and replaced the valve but nothing. I disconnected the battery the whole night and that reset the computer and it kinda of works now. At least it's not accelerating anymore like it was bfore.

Kinda works now? What's it doing? Does the engine act weak?

well, whenever i turn it on it iddles correctly now. I've yet to drive it lol. I'll try to drive it this afternoon and we'll shall see.

ok, i had been driving my indy for a while without a problem until today. I  went to turn on the car and it wouldn't turn over at first and when it did it iddle high 5,000rpms and it kept climbing up so i turned it off. It gave a code 35 which i know has to do with the iddle but what else besides the iac could be causing this problem? could it be my ecu or perhaps map sensor? it turn on now whenever i crack it but it iddles high. how can i find out? thanks guys.

ok, i had been driving my indy for a while without a problem until today. I  went to turn on the car and it wouldn't turn over at first and when it did it iddle high 5,000rpms and it kept climbing up so i turned it off. It gave a code 35 which i know has to do with the iddle but what else besides the iac could be causing this problem? could it be my ecu or perhaps map sensor? it turn on now whenever i crack it but it iddles high. how can i find out? thanks guys.

The computer may be in LIMP mode.
Disconnect battery and run Code scan. Is it shooting an SES light?
You can use simple Code scan procedures with the Stock 90.

Sorry man, lost track of this. Did you change the TPS? Yea, got to back 2nejunkie. Have you lost anything else(speedo or AC etc.)? That would be the ECM for sure. I'll have to look up the code. The IAC can't give the engine that much air to run at 5000. Out of time, sorry again.

yes i replaced the aic, haven't replaced the tps yet but i will. Yes i got the ses light on and troubleshot it and it gave me a code 35 which is iddle circuit or something. The question is where in the circuit would i have to look for signs of trouble? like i said the aic is new so i don't think it's that. I will replace the tps and maybe the map as well. It's just really annoying that it worked fine but now runs like crap.  

try unplugging the electrical connector from the MAP sensor, when you do that the computer will substitute a known value based on the IAT sensor and TPS. it'll set a MAP low voltage code, but you'll know if its the problem cause it'll run better.
if you had a bad cat (inefficient) it wouldn't run bad, it just would pollute more. if your cat was plugged it would drive ok, but it would accelerate poorly and wouldn't rev high at all.
so check the MAP, I don't think the TPS is at fault, they get dead cells and cause problems as you put your foot down on the gas.

Ok, in an old book I found Code 35. Under that it has Idle Speed Error. It talks of testing the IAC(you have a new one),so forget about that. It does say to test the wires(20 ohms is what it has in the book). It goes on to say if everything checks out replace the ECM. I thought you did that before.

replacing the ECM is always the last step in those flowcharts. those ECMs got replaced alot of times because of poor diagnostics. check everything, check the resistance of the wires, shorts to ground, and shorts to voltage. check each connector in the circuit to make sure that terminals have not come out of the connectors. just check every little thing you can think of, I just don't want you to spend the money and then find out that it wasn't the ECM. GL!