Intermittent poor/no idle, and bucking

[Comanche1]

Ok…  suddenly, I have an intermittent poor or no idle and when it does this, vehicle bucks. Then just as suddenly, it clears up! 2.5 4 speed. I’ve replaced both fuel relays. Fuel filter, put in some gas line antifreeze, new plugs, cap rotor. I’ve got a new map sensor to install. Any one experience this sort of thing?

[89 MJ]

Maybe an issue with your ISA. How clean is your throttle body?

[cruiser54]

Have you ever refreshed the braided ground wire at the firewall? What is its condition?

 

Intake manifold bolts loosen up. The vacuum lines under the throttle body deteriorate. 

[Comanche1]

On 2/25/2024 at 4:14 AM, cruiser54 said:

Have you ever refreshed the braided ground wire at the firewall? What is its condition?

 

Intake manifold bolts loosen up. The vacuum lines under the throttle body deteriorate. 

Because it comes and goes, it is perplexing.  Everything under the hood looks good.  The only thing I can’t see is the egr operation, I’ll lube it up when I get home!

[cruiser54]

You can't refresh grounds and tighten loose intake fasteners by "looking". You must perform the tasks. 

[Comanche1]

On 2/25/2024 at 4:14 AM, cruiser54 said:

Have you ever refreshed the braided ground wire at the firewall? What is its condition?

 

Intake manifold bolts loosen up. The vacuum lines under the throttle body deteriorate. 

All good with the braided wire.  It’s so intermittent. One minute it’s perfect then stalls and bucks.  Today I got a smell of running too rich. 

[Comanche1]

What can cause a intermittent run rich situation?

[cruiser54]

Describe "all good". Did you remove it from the firewall, scrape the paint to bare metal, sand the braided cable where it attaches to the firewall and then tighten it up? 

 

We understand it is intermittent. This is how you deal with intermittent problems. do stuff. 

 

Have you visited my website and COMPLETED Tips 1 through 5 yet?

 

[Comanche1]

On 2/28/2024 at 2:02 PM, cruiser54 said:

You can't refresh grounds and tighten loose intake fasteners by "looking". You must perform the tasks. 

All done about 2 months ago as part of annual maintenance 

[cruiser54]

Tips 1 through 5 completed? Including c101?

 

[Comanche1]

On 2/29/2024 at 6:20 PM, cruiser54 said:

Describe "all good". Did you remove it from the firewall, scrape the paint to bare metal, sand the braided cable where it attaches to the firewall and then tighten it up? 

 

We understand it is intermittent. This is how you deal with intermittent problems. do stuff. 

 

Have you visited my website and COMPLETED Tips 1 through 5 yet?

 

So I followed your suggestions. Didn’t know about your website! I’ll definitely check it out. My history is a master mechanic for the last 40 years, owned our own shop in Kelowna bc for years. I have Zero experience with renix anything. After a good drive today, I detected it seems to only happen off idle but perfect at almost all other throttle positions. Plenty of power on the highway, so I know fuel delivery isn’t an issue. TPS?

[Comanche1]

Just now, Comanche1 said:

So I followed your suggestions. Didn’t know about your website! I’ll definitely check it out. My history is a master mechanic for the last 40 years, owned our own shop in Kelowna bc for years. I have Zero experience with renix anything. After a good drive today, I detected it seems to only happen off idle but perfect at almost all other throttle positions. Plenty of power on the highway, so I know fuel delivery isn’t an issue. TPS?

How do I find your website please 

[cruiser54]

www.cruiser54.com

[Comanche1]

Ok , your website is awesome. Many thanks. 

[cruiser54]

Complete Tips 1 through 5 right off the bat.

 

Make sure the intake manifold bolts aren't loose and the vacuum lines are in good condition also. 

[Comanche1]

True. I’ll check all of this when the weather permits. 

[Comanche1]

Followed all your recommendations. Based on test results, I popped in a used TPS I had. Now running perfect again. Many thanks again.