ive been working on a 68 hemi roadrunner all day, trying to finish the EZ EFI swap. it starts and idles great, but anytime you pull it into gear (automatic), it lurches and dies. the idle is set at 1000 RPM. it feels like when you are sitting at idle in a stick car and let out the clutch. just lurches and dies. if you start the car with it in gear, about the time it starts running, it starts moving. then dies out, like its being bogged down by being in gear.
after talking with FAST for a long time, and trying everything from relearning the computer to fooling the IAC, to having the idle set at 2000RPM, they said the car had a bad torque converter. does this sound right? is there any definate way to diagnose a bad converter without dropping the trans?
thanks
Michael
If it were anything other than a Mopar, you could unbolt the converter and let it spin free. Mopar has the ring gear on the converter, not the flex plate.
Push it down a hill ( Car can't be worth too much, right?
)until you hit 20 mph, then pull it into gear. See if its fine until you try to stop.....
You haven't got some wiring or hydraulic issue with a modern lockup converter? What trans?
Yerall fBerkleyed up son , splain yerself . manumatic or auto tragic? How many pedals does this car have?
OK nevermind, where was that beat up rusty spitfire?
If it ran ok before the FI conversion it should not be the torque converter.
It sounds like that when the car is put into drive the load from the transmission is dragging the engine down to the point of stalling. It sounds like the IAC is not stepping up the idle to compensate for the transmission load. BTW, does this engine have some sort of radical cam?
I too say IAC problem, but if you did a cam swap, reused the TC without restalling it, and you have increased the torque or changed the powerband higher, the converter is going to stall LOWER then before.
One other question, are you sure the bands are adjusted properly? Just wondering if the trans is binding up internally causing additional drag and therefore the stall, or possibly a bad pump.
Put the transmission in drive. Turn the engine by hand.
This will tell if something is locked up.
Then go from there
the car has a fairly aggressive solid roller cam in it. pulls 12 in vacuum at 1100 RPM idle.
due to my various threads on this topic, ive got some ideasd to try.
the car had started to die out when coming to a stop at the end of last summer according to the owner, and hes never had a good idle. could not get it to idle in gear this year, hence the FI conversion. he drove it to my house by shifting it to neutral and revving the snot out of it at stoplights.
first step is going to br checking his base timing and seeing where thats at. get it set correctly if its not, then relearn the efi setup.
also going to check for good spark.
already confirmed no vaccuum leaks.
if the car still dies out when put in gear, jack up the rear end,put it in gear, and slowly apply the brakes and see if it still stalls.
the fluid in the trans is burnt, so im not putting trans out of the question. i just want to make sure that its not my EFI install that he just paid me to do screwing up.
am i missing anything in my checkup?
i rarely work on cars with automatics. so the engagement into gear stalling problem is new for me. the last 3 cars i converted to fuel injection
were all stick shift, and 98% of the cars i work on are as well.
is there anything else in the tuneup that i may be missing, or the diagnostic chain?
Michael
Could it be that your fuel map is just too lean?
Dusterbd13 wrote:
the car has a fairly aggressive solid roller cam in it. pulls 12 in vacuum at 1100 RPM idle.
the fluid in the trans is burnt, so im not putting trans out of the question. i just want to make sure that its not my EFI install that he just paid me to do screwing up.
am i missing anything in my checkup?
That is still a decent amount of vacuum at idle. When you get into the single digits, is when you really have to be on your game...
If the fluid is burnt, I am 85% sure the clutches are burnt and when applied don't release because of accumulated garbage hanging up the sliding of the clutches in the drums plus the changed viscosity of the ATF. I had to drive a rental box truck once with a smoked trans in it, it would want to stall coming to stops. It sucked to stop at every street corner to deliver newspapers to carriers.
I think you have everything else covered.
The torque convertor should still allow the engine to idle, unless it has a lockout clutch which is not releasing.
I wonder about the 12" vacuum. Seems low even with the cam.
