My brother fixed a bad exhaust leak on the turbo (bolts missing
between the two halves of turbo body). Now when he starts it up, the
car won't idle right, the idle surges between 1000 to 3000 RPM. What
could he have done to screw it up? I told him to look for some sensor
they might have inadvertently disconnected and read out the codes.
It had been setting a code for a bad O2 sensor. He is going to try
replacing it, but I can't see this having any effect on the idle from
initial cold start...and it has been setting this code for a long
while prior to the turbo repair, and had a smooth, correct idle.
Any ideas?

Correction: he says it doesn't hunt wildly until the engine gets hot.
It is also overheating within about 15 min at idle, but engine fan is
running. He recently had the radiator checked and reinstalled it. The
first day after reinstalling it, the car ran fine, so it is nothing to
do with the way he installed the radiator. The upper hose gets hot
within a minute or so of start-up. I told him to remove the
thermostat...he did but there it still iverheated quickly. He says
when it overheats, he loses colant out the (new) reservoir tank. It
must be lsing out the pressure relief on the cap, he says there are no
apparent leaks on the reservoir. It just builds up tremendous pressure
when the car overheats.
The day before he repaired the turbo, I checked the engine temp
with a digital IR thermometer gun, and at the thermostat housing, the
temp was regulating (by the fan turning on/off) at about 210 Deg at
idle. He says he doesn't see how they accidently dosconnected any
sensor.
How else can we flow-check the coolant other than the upper-hose
heat check?


On Sun, 29 Oct 2006 06:06:18 -0600, geronimo <Jamesw (AT) grandecom (DOT) net>
wrote: