1999 Ford Escort

this usually means that there is a internal engine vacuum leak.

also check the pcv valve to see if it is clogged.

[quote:9d212d592c="mastertechtim"]this usually means that there is a internal engine vacuum leak.[/quote:9d212d592c]

Tim, thank you for your advice, but how do I check to see if there is an internal vacuum leak?

id check the pcv valve first

[quote:02d3954d2c="mastertechtim"]id check the pcv valve first[/quote:02d3954d2c]
Tim:
I checked the pcv by blowing from one side and then blowing from the opposite side, air went through easy
from one side but not from the other side. I believe it is
ok, but please correct me if I'm wrong. thanks. Rey

ok rey im trying to remember this engine set up. are you having a problem with the car? lets not make a problem out of something if theres not a problem. removing the oil cap may affect the readings of the mass air flow sensor causing it to stall. is the check engine light on? is it burning oil? any other symptoms? get back to me

[quote:d5f25dd53c="mastertechtim"]ok rey im trying to remember this engine set up. are you having a problem with the car? lets not make a problem out of something if theres not a problem. removing the oil cap may affect the readings of the mass air flow sensor causing it to stall. is the check engine light on? is it burning oil? any other symptoms? get back to me[/quote:d5f25dd53c]

Ok Tim, I'll give you the complete story. I took the car to emissions, didn't pass, the check engine light is on, so I took it to a repair shop, the guy there examined it and He said it had no oil at all, I had checked the oil about 4 days prior and it was ok, so I was really confused and then he showed me the oil cap thing, that the engine stall when taken off, and it did! he then told me the compression had reversed. then I decided to write you and here we are. I hope this helps with the diagnosis thank you so much. Rey
PD funny thing is it runs real nice...

ok. lets start by getting the car scanned and find out what code you have. autozone will do it for free. then ill know better what the next step should be.

[quote:c0a628db41="mastertechtim"]ok. lets start by getting the car scanned and find out what code you have. autozone will do it for free. then ill know better what the next step should be.[/quote:c0a628db41]

Hi Tim, I finally got around to taking the car to autozone, to scan for the check engine light. Here are the results:
Code P0135: Malfunction in the heater circuit for oxygen sensor 1 in bank 1.
Code P1451: Evap system canister vent solenoid circuit malfunction.
Code P1506: Idle Air Control overspeed error.
Hopefully this info will help us to find the problem. Thanks, Rey.
I almost forgot to mention that I have replaced both oxygen sensors. does it have more than 2?

disconnect idle air control valve and see if idle changes. code 1506 is set when the computer tries to lower idle and the idle air control valve wont let it, this is either caused by a bad idle air control valve or a vacuum leak. did they clear the codes? you need to check out the idle one first and get to the bottom of that.

[quote:845b33bccd="mastertechtim"]disconnect idle air control valve and see if idle changes. code 1506 is set when the computer tries to lower idle and the idle air control valve wont let it, this is either caused by a bad idle air control valve or a vacuum leak. did they clear the codes? you need to check out the idle one first and get to the bottom of that.[/quote:845b33bccd]

Does this mean that when you disconnect the idle air control valve, the idle is supposed to slow down or pick up speed? Any way I did disconnect it and nothing happened, I looked to see if I could find a vacuum leak but I found none.