Help...my car will not idle... continued.

[danalyse]

Did a top end job about 3K ago and it was running great. A couple hundred miles ago it developed a very slight rough idle. In the past few miles things have deteriorated rapidly to the point were it will not idle at all. The OBDI shows no fault codes 1444. My under the hood Peake diagnostic reader seems to says it is the Lamda sensor but the check engine light is not on. Any ideas...please.

[XXXSkyGuyXXX]

is it a vacuum leak?

[danalyse]

I thought about a vacuum leak. For the heck of it I replaced the air filter and it got worse.any suggestions what I should look at? Thanks.

[XXXSkyGuyXXX]

if U'r not sure U can run a smoke test and see if U do have a leak or not

[XXXSkyGuyXXX]

do U have the is or es?

[danalyse]

I think it is a plain old. A cabrio marked M-Technic.

[Jaxx_]

spark plugs look okay?

[dnguyen1963]

Rough idles equal vacuum leaks most of the time. Perform a smoke test.

[jlevie]

Yep, have a smoke test run.

[danalyse]

Idle problem continues...help!

Replaced boot between throttle body and airflow unit as it had some dry rot but no improvement. I can start the car and get the RPM up to the mid teens to keep it running but then the RPM slides down to around 500 RPM and eventually will be rough and stall. The consensus seems to say vacuum leak...anything specific to look at. Any chance a bad oxygen sensor can cause this as my under the hood diagnostic tool says that is a problem but the OBDI system does not.

[jlevie]

If the engine won't idle when cold, the O2 sensor can't be the cause. At that point the DME is in open loop mode and not using the O2 sensor data.

As far as intake leaks, the specific things to look at are where you see smoke leak out during a smoke test.

[danalyse]

Is my idle problem solved?

Borrowed a fuel pressure tester from the auto parts store. Placed a T in the line to the fuel rail and cranked the engine. The gauge does not move. Seems like a bad fuel pump? What do you think?

[Jaxx_]

if you're sure you got the right fuel line, yes.

Does the fuel pump whine at all?

[jlevie]

Are you sure you have the gauge on the supply side? That is the hose that connects directly to the rail. The hose that connects to the FPR is the return line and will be a zero pressure.

If you have zero pressure in the rail, the engine won't fire or run at all.

[danalyse]

Fuel pressure saga continued.

Clearly hooked up to the rail. I'm assuming there is a little pressure but it is quickly bled off when starting the car which only runs for a few seconds. Can't hear anything running from under the rear seat. Should I pull the rear seat and listen. Should I hear the pump when the car is not running? Is there more than one pump? I have replaced the fuel filter within the past 3K.