I just purchased this car and have done alot of work to get it running. Now that it is running it will idle for about 10 till warm. Soon after the idle will dip down to 300-500 rpm and just die. Sometimes it will start right back up and idle to 1500-2000 and drop back down to 900. It will run this way for about a minute and die again.

Sometimes after it dies I need to hold the starter engaged for 3-5 seconds until the engine fuel engages and starts.

Again sometimes before it dies the idle will fluctuate 1000-1500 up and down till it dies.

Previous work---Water pump, timing belt, heads resurfaced and all new gaskets.

The air intake tube is all taped up like it had a previous tear. If I didsconnect the crankcase breather tube the engine still runs so I dont supspect a tear in the tube as being the culprit.

I do suspect the mass air flow sensor, but its expensive. The reason I suspect this is I know if you disconnect it the engine will die imediatly. One time I was taping on it and the car died.

PLease HELP!!!!!!

 

Disconnecting MAF and engine quitting sounds normal (mine dies), however cleaning the MAF & throttle body may help: Rough Idling Issues |*MotorWeek (play video). if it's not connected good, it may be a problem. wrapping big nylon ties around the intake helps.

it will idle faster when you first start car normally.

is your check engine light on? if so, go to shop and tell them to tell you the hidden codes.

vaccuum leaks will do this as well as a stuck EGR valve.

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what engine? if i disconnect the mas on our 2.3's, the car will still run, but rough. most cars will run with the mas disconnected. have you checked your icv(idle control valve). this valve has a LOT to to with idle, and part throttle. it allows more air when in cold start mode, and when other accessories like a/c put a load on the engine, it will control idle. vacuum leaks are common on the 2.3, and will cause all kinds of problems. is the check engine lite on, and if so, what codes are stored?

 

I have a 2.5 liter. The car does not have a check engine light that will light up by turning the ignition to the on position. I suspect the bulbs are burned out. I am afraid to drive it to the shop due to it stalling. I noticed it does have a OBD2 connector but this is an OBD1 car. Are these the same as the OBD2?

 

if it has the connector, then it should scan. so far, every 95 owner has been able to get it to scan if the car is a usa car. i think the other forum, which i see you also posted on, has a link to the wiring diagrams for a 95. dunno if 95 had a ce lite, but if it does, perhaps the po taped it, or pulled the bulb to hide it from potential buyers. i always take my scanner and plug it in. i like to know what problems there are before i buy

 

Well I changed the mass air flow sensor and no changed. I will say it seemed to run longer before the stalling out, but it still dies. Im going to try seaform in fuel and cleaning the throttle body. I dont think its a vacuum leak because it will run great for 20 minutes at idle.



Please keep sending ideas.

 

When you make changes you should re-set computer by disconnecting the negative terminal followed by applying pressure on brake pedal. Idle car for 10 minutes before driving. You'll need to drive at least 50 miles for re-learning (over a few days is OK).

 

Ive checked the egr control vacuum solinoids and prc solinoid. They all seem bad. The prc soolnoid wont operate by power supply, its wide open all times. The two virs valves... One works, but clogged and the other wont operate.

Will these vavle really mess with engine running, and if so is there a way to bypase them so engine runs good?

 

Well I changed 6 vacuum solinoids which were bad. This has so far fixed the problem!!!

I went through 3 complete mazdas at Pull-A-Part and was only able to find 6 which were good. This is obviously a problem with these older mazdas.

Its easy to see if yours are bad. Simplay ohm between the 2 electrical posts and you should get 40-60 ohms. If they are open, they are bad.

BE CARFULL OF THE VACUUM TUBES, THEY ARE FRAGILE!!!