Speedtoys

I'm having something come up more than it used to..It used to be just..once every few months. Now it's happened 2x today.

Im currently in Houston.

The car will want to stall touching the throttle off idle, and when this happens RPMs just fall, not like a bad CPS, but the engine 90% stops running right away..hufs 5 or 6 compression stroked..and then comes back, or dies.

When it dies..to restart it I have to go WOT, and its just pig rich, fuel smoke and all..and it will stumble a few seconds, and then run ok, have never had a hiccup in cruise, just coming off idle, and a hard start if it dies.

LH going out?

Tony

have a sharktuner handy? sounds like a TPS to me?

Speedtoys

I..will in Denton Friday.

But FML if I'm going to replace that by myself on the road..

Tom. M

is the MAF new or rebuilt? Check operation by disconnecting to see if it changes this behavior. A bad MAF will run at idle and at around 3k rpm fine but like crap everywhere else.
Doesn't sound exactly like your problem, but something easy to check..
One other thought, Temp 2 sensor?

Speedtoys

MAF is rebuilt, 2016 from Roger.
TPS is new 2019 @Precision.

jcorenman

Jeff, this smells like MAF to me.

Speedtoys

Off-idle MAF issues...that's new to me, but I don't follow all of the MAF threads.

I -should- make it to DFW Friday, where I can visit the Church Of The Roger...

chart928s4

+1 for possible TPS. That sounds like the behavior my car had - stall at idle when warm, no problem when cold or under power. TPS was defective initially, then installed wrong by a newbie (me), both times issue confirmed by Bosch Hammer, corrected by repositioning/rotating the switch. Could probably be a bunch of other things as well.

Mrmerlin

Have the LH computer been rebuilt?
if its firing then the CPS should be OK.
whats the condition of the MAF connector
have the 4 running relays been replaced?
are the battery terminal tight?
whats the running voltage at the hot post?

NOTE you can test the relays in position just ID the location the put your finger on each one,
you can feel them click when you turn the key to run or after cranking.
NOTE kneel on the ground with the CE panel cover removed and crank with the left hand with right hand on the relay

Speedtoys

I have no maint records of a new LH, and I have a TON of records
Connector seemed fine last I saw it a year ago
Relays..I believe so, will double check, but I absolutely will in DFW this weekend.
Battery is solid and tight..cable has been replaced as well...and ground.
I don't have a DVM handy here in Houston, will in DFW.

Speedtoys

This will IDLE fine, but bring it off idle, it will fall down and die, then seem VERY fuel rich when restarting.

GregBBRD

MAF, bad connection to temp sender, or bad damper./regulator.
In my experience the LH either works or it doesn't and the throttle switch can't dump that much fuel without a corresponding big airflow signal from MAF.

Zirconocene

I'm sure there are multiple ways for our cars to do what yours is doing but what fixed mine is new dampers and FPR. I don't know which one of them was the culprit but they all got switched out and now everything is humming. Not as it should, mind you, there's a ton of work that I'm sure is still needed, but this stumbling thing right off idle is gone. On my car, it was subtle, but every so often I could feel a little bit of a stumble while cruising. With the engine above 1k rpm it never outright died, but it would have at idle!

ETA: Or what @GregBBRD said.

Good luck, you're headed in the right direction for some solid help and support.

Cheers

Speedtoys

Both temp senders are new, and have new, super clean and tight connections. Cleaned those up from their sad state Fall of 2019.

Weird that maf only does this..at this coming off idle area.

Speedtoys

Ill go sniff around the dampers/regulator while it cold too today. These are new as of..2018?