115 BLM at hot idle....

[Missouri T]

Hi folks,

Let me start by saying my car is running fantastic other than:
1. A (what feels like a) slight miss at steady state speeds (125-128 BLM)
2. A little stumble when it comes to a stop (RPM's drop down and recover).

When I come to a stop, idling and hot the BLM's are at 115.

Fuel pressure is at 43PSI with the hose off, per my Turbo Tweak pump gas chip.

Should I drop fuel pressure?

Other than that, she's running fantastic.

Thanks in advance for any and all input.

 

[kmarino]

hey bill its kris bought your grey t awhile back nice to see you got another! anyway i guess have you checked for possible vacuum leaks as far as the stumble

 

[Missouri T]

hey bill its kris bought your grey t awhile back nice to see you got another! anyway i guess have you checked for possible vacuum leaks as far as the stumble

KRIS!!

Long time no talk!

I am sending you an e-mail right now.

I'll check the vacuum lines again.

But the 115 BLM's at idle? Any ideas?
It's easy enough to adjust fuel pressure so I'm willing to try that, too.

 

[VadersV6]

What are your IAC counts at hot idle?
How do your plugs look?
Ohm test all your plug wires and ohm test the coils. Front to back...should be around 11k to 14k ohms. The plug wires should all be fairly close to each other.
How do your o2 crosscounts look? Are they cycling from 0 to 255 within 90 seconds?
Check the counts for IAC and o2's after the engine is warmed up AND its running in closed loop.
Also, this is a big one that everyone should do. Get a 1/2" to 3/4" heater hose, and listen at the base of each fuel injector and all around the mating surfaces where the intake manifold meets the heads, all around the vacuum block and any other hose connections you can access. A mechanics stethoscope wont pick up vacuum leaks and the propane test is worthless. A vacuum leak will be VERY audible through the hose.
Check every hose, everywhere, for cracks. Replace as many as you can and hose clamp everything you can. Make sure all the hose clamps after the MAF are tight and the silicone tubes are in good shape.
Pop the PCV valve out and shake it to make sure the flapper is free and flush it out with alky in both directions.
Adjust/set all the sensors. Just for kicks, pop the #1 plug out and rotate the motor till air starts pushing out pretty hard (compression stroke). Pop the cam sensor cap off and make sure the window on the brass colored ring is facing somewhere toward the air filter.
Look at the back of the passenger side head and make sure the ground wires are clamped down well. You can see it best from under the car.
Even though your issue is probably 1 or 2 things, doing all of the above will make the car run even better and give you peace of mind.

 

[Missouri T]

Thanks for the response, Vader!!!

What are your IAC counts at hot idle? Between 18-25
How do your plugs look? Replaced them about 50 miles ago.
Ohm test all your plug wires and ohm test the coils. Front to back...should be around 11k to 14k ohms. The plug wires should all be fairly close to each other. Coil pack is new AC/Delco and all tested around 12.5K. But I have not checked the plug wires.
How do your o2 crosscounts look? Are they cycling from 0 to 255 within 90 seconds? THAT is a good question!
Check the counts for IAC and o2's after the engine is warmed up AND its running in closed loop.
Doesn't my Turbo Tweak chip run in Open Loop at idle? They tend to be pretty high-in the 800's.
Also, this is a big one that everyone should do. Get a 1/2" to 3/4" heater hose, and listen at the base of each fuel injector and all around the mating surfaces where the intake manifold meets the heads, all around the vacuum block and any other hose connections you can access. A mechanics stethoscope wont pick up vacuum leaks and the propane test is worthless. A vacuum leak will be VERY audible through the hose.
Now THAT I haven't done!
Check every hose, everywhere, for cracks. Replace as many as you can and hose clamp everything you can. Make sure all the hose clamps after the MAF are tight and the silicone tubes are in good shape.
Just did that when I replaced the plugs.
Pop the PCV valve out and shake it to make sure the flapper is free and flush it out with alky in both directions.
Did that with the plugs as well.
Adjust/set all the sensors.
Checked when I replaced the plugs. Trust me, they're spot-on.
Just for kicks, pop the #1 plug out and rotate the motor till air starts pushing out pretty hard (compression stroke). Pop the cam sensor cap off and make sure the window on the brass colored ring is facing somewhere toward the air filter.
Haven't done THAT yet!
Look at the back of the passenger side head and make sure the ground wires are clamped down well. You can see it best from under the car.
I have a large master ground on the firewall up high near the coil pack area.
Very clean and neat.
Even though your issue is probably 1 or 2 things, doing all of the above will make the car run even better and give you peace of mind.

 

[VadersV6]

Thanks for the response, Vader!!!

What are your IAC counts at hot idle? Between 18-25
How do your plugs look? Replaced them about 50 miles ago.
Ohm test all your plug wires and ohm test the coils. Front to back...should be around 11k to 14k ohms. The plug wires should all be fairly close to each other. Coil pack is new AC/Delco and all tested around 12.5K. But I have not checked the plug wires.
How do your o2 crosscounts look? Are they cycling from 0 to 255 within 90 seconds? THAT is a good question!
Check the counts for IAC and o2's after the engine is warmed up AND its running in closed loop.
Doesn't my Turbo Tweak chip run in Open Loop at idle? They tend to be pretty high-in the 800's.
Also, this is a big one that everyone should do. Get a 1/2" to 3/4" heater hose, and listen at the base of each fuel injector and all around the mating surfaces where the intake manifold meets the heads, all around the vacuum block and any other hose connections you can access. A mechanics stethoscope wont pick up vacuum leaks and the propane test is worthless. A vacuum leak will be VERY audible through the hose.
Now THAT I haven't done!
Check every hose, everywhere, for cracks. Replace as many as you can and hose clamp everything you can. Make sure all the hose clamps after the MAF are tight and the silicone tubes are in good shape.
Just did that when I replaced the plugs.
Pop the PCV valve out and shake it to make sure the flapper is free and flush it out with alky in both directions.
Did that with the plugs as well.
Adjust/set all the sensors.
Checked when I replaced the plugs. Trust me, they're spot-on.
Just for kicks, pop the #1 plug out and rotate the motor till air starts pushing out pretty hard (compression stroke). Pop the cam sensor cap off and make sure the window on the brass colored ring is facing somewhere toward the air filter.
Haven't done THAT yet!
Look at the back of the passenger side head and make sure the ground wires are clamped down well. You can see it best from under the car.
I have a large master ground on the firewall up high near the coil pack area.
Very clean and neat.
Even though your issue is probably 1 or 2 things, doing all of the above will make the car run even better and give you peace of mind.

Yes, turbo tweak runs in open loop at idle. Thats one thing about that chip I dont like.
You replaced the plugs 50 miles ago...ok. How do they look, lol?
Since you recently did the hoses, check them again.
Pop the EGR diaphragm hose off of the diaphragm and see if there is air sucking. There shouldnt be. With the motor off, pull up on the diaphragm from underneath, then plug the barb with your finger and let go of the diaphragm. Does it drop? It shouldnt.
Check the EGR solenoid's filter.
I have a power supply at work so I dont know how you'll do it...maybe find a switched 12v power source on the car and cycle the charcoal canister solenoid (with it removed of course...dont lose the o-ring!). I found that mine was sticking. I kept cycling it, spraying WD-40 in the inlets and blowing it out with an air gun, and it eventually started cycling properly again. I also made my own brass/spring/ball bearing (RJC boost controller style) check valve for the charcoal canister. The replacement ones dont work all that great. Also check the hoses that run to and from the canister. One hose rubs up against a sharp edge and can wear through.
Go out on the road and enable cruise control if you have it. Go park the car and wait 10 minutes, and pull the vacuum line off the cruise control vacuum diaphragm. If it's sealed well, the vacuum in the system will purge. Otherwise you may have a torn cruise diaphragm.
You have a master ground on the firewall...how is the block itself grounded? Is it still hooked up to the head?
Having a big master ground close to the coil pack isnt a good idea. You could have some EMF issues screwing the coils/ignition module up.
Is your IAC motor screwed in tight? I found mine was loose a few months back. I could turn it by hand.

 

[Missouri T]

Everyday is an adventure with a TR.....

I was out in the car all day today.

Something I found is that it runs a LOT better with the A/C on.
No stumble when you come to a stop especially.
BLM's hover at 120 with the A/C on, rather than 115 when it's off.

BUT the BLM's are still 115 at hot idle.

AND a couple new twists were added today:
1. The IAC numbers are in the 80's!?!??!? They were perfectly in the high-teens to mid-twenties before.
2. The idle speed is at 700-750 now. It was at the chip preset of 800.
BAD IAC? It only has 6300 miles on it.

I went over the vacuum hoses and am confident they're alright.

The spark plugs are spotless. Just like new.
The plug wires are 10mm Magna's and averaged 1500 ohms/ft..

Can a leaky/stuck injector cause these BLM/idle issues?
My 42.5# Lucas's are only 6300 miles old but you never know...
Is there a good way to test them in the car?

I replaced the 3 wire heated O2 sensor for the heck of it.
The CC's sped up a lot but the previous O2 wasn't bad.

I'm really sick of working on the car but it's become laughable anymore.
As I said in the title, "everyday is an adventure with a TR....".

Thanks for all the input!

 

[knucklehead]

Had The Same Problem Bad Injector!! Brand New Right Out Of The Box