Hard Start, Rough Idle and a little noise by the timing chain cover

[carlc376]

Hi all, I am new here. I am working on my Mom's 2006 Vibe 1.8 (2wd, 1ZZFE, Auto, 204,000 miles). The car was bought used with only carfax history, which did not show any major engine repairs. Oil changes were shown and did appear to be fairly consistent.

The Problem:
1. Everytime the car needs to be started, it requires several seconds turning the key to get it to start. This duration appears to be very consistent. Yet, it always starts eventually. Code scanner reveals no codes (no Check engine light either). It has never stalled, even though it acts like it might want to.
2. Rough idle (Seems fine when throttle is applied)


I have replaced the following:
Throttle body gasket
Intake manifold gasket (Orange gasket)
Valve cover gasket
Spark plugs
Motor mounts (were bad, but no change in idle feel)


Possible fixes I found (I am trying to avoid my Mom throwing a lot of money at the problem and still not fix it.)
- Fuel pump (Seems like this would have a code associated to it)(Maybe the pressure regulator or check valve?)
- Timing Chain tensioner (I may just do this since it is inexpensive)(There is a slight rattle near where the Tensioner is located.)
- PCV (I may just do this since it is inexpensive)


Any thoughts on this are appreciated. Thank you in advance.

[carlc376]

Update to my post. The bulk of the vibration is only felt while the car is in Drive/Reverse. In park or neutral the idle seems fine. I have replaced the PCV and the timing chain tensioner.

Any thoughts on why the rough idle is so predomininate while in gear?

[andrewclaus]

One tune-up item you haven't mentioned is cleaning the MAF sensor.

Otherwise I'd start checking engine mechanical health--compression or bleed-down test.

Did you fix the hard start issue?

Did the timing chain tensioner solve the noise? I replaced mine for an oil leak, and the engine got a little quieter.

I haven't experienced the rough idle issue with the Vibe, but from reading other posts here it sounds like it's a tough problem for some.

[Jbenrod]

How about checking out the motor mounts. Start by looking at the rear one (that is near the firewall). I think you can see it best by removing the LF tire and looking at it from that direction.