1998 Ford Escort motor runs when map is disconnected

PEDRO06

MEMBER
1998 FORD ESCORT
4 CYL
2WD
AUTOMATIC
111,210 MILES

The cars started running rough and then one day it stopped we replaced the plugs and wires and the Idle air control valve. The mechanic checked everything and he doesnt know what it is. We had a mechanic check the computer and he said it doesnt show anything wrong. He said it might be the computer is not sending the correct info. It does not run when the map connector is connected but does when it is not disconnected. The mechanic changed it out with another map and it did the same thing.

4 Replies

MERLIN2021

MECHANIC
17,250 POSTS

Do you mean the MAF sensor in the air filter box?

Was this

answer

helpful?

Yes

No

Monday, January 25th, 2010 AT 2:38 PM

PEDRO06

MEMBER
2 POSTS

Yes the air intake module or controller that is in the air filter compartment. It has wiring coming out of the air filter compartment from a sensor or something and when the connector for the wires is plug in the car dies. When I unplug it the car runs. The mechanic that looked at it said the computer was not showing that there is something wrong but obviuosly there is. He replaced it with another used one he had but it still did the same thing.

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

Tuesday, January 26th, 2010 AT 2:59 AM

MERLIN2021

MECHANIC
17,250 POSTS

Ok so no codes present, means for whatever reason the PCM isnt sensing the MAF as unplugged? I will look up the wiring diagram and see which wires we need to test on this.I need to know if it's a sedan(4 door) Wagon or coupe?

Was this

answer

helpful?

Yes

No

Wednesday, January 27th, 2010 AT 2:19 PM

MERLIN2021

MECHANIC
17,250 POSTS

Org/Blu=MAF return signal line, White/red=PCM power relay in the CCRM(constant control relay module) Most likley the problem...Brown/Black=PCM IN, Black/Yellow= Ground, another possible source.
Unplug the PCM connector and check the OHMs of the Or/Blu and Brn/Blk wires put one end of the teser on each end of the wire, and reading should be less that 5 ohms, if higher or OL is displayed, there is a short or break in the wire. Probe the Yel/Blk with one lead and ground the other, same readings apply 5 ohms or less. Test White/Red the same way. This is for a normal 2.0 escort, not a ZX2

Was this

answer

helpful?

Yes

No

Wednesday, January 27th, 2010 AT 2:39 PM