geo tracker like to bog out.

[danknugs87]

Hi. I have a 1992 Geo tracker that is having a problem. It starts fine and drives fine until about 2or 3 miles down the road. It will run fine until I have to slow down. Once I slow down and begin to shift again it will bog down. once it is at 2300 rpms or so in each gear the bogging goes away. also some times coming up to stopsigns it will just completly die and I will have to let it sit for about 5-10 minutes before it will start again. I have done a full tune up new plugs,wires, cap, rotor, o2 sensor. I have also within the last 7 months done a gas tank, fuel pump, fuel filters, new exhaust, oil change, and new air and oil filters. If anyone could help it would be greatly apreciated.

[jtgh]

8v or 16 valve head.?
EFI is very different, on each.
but,
when it dies ,did you try to find out of you have spark and fuel.
on either 8v or 16v.
have spare clean (not fouled plug in pocket) then when it dies and wont restart.
remove #1 wire at plug ,swap in good plug and see if you get a fat blue spark.
let shell of plug rest on valve cover for ground (touching sell to metal)
if you are not lossing spark ,then it is fuel.

( my ESP,says your caps are bad, in ecu, after all its a 92 and they all go bad that year)
The Ecu crashes with bad caps and makes for digital anarchy.

the ECU will drop the IDLE controls anytime there are serious problems.
nice tune up, you have a solid base there. should help greatly.

IAC sticking , will not cause problems off idle, It is shut down off idle.
on a 16v you could have cracked air hose on top feeding the IAC/ISC valves letting in illegal air. illegal air on 16v is very very bad.
let me define illegal air, that is any air on a 16v ,that did NOT enter and pass thur the MAF sensor.
IAC = idle air controller valve. (electric modulated)

i presume you still have a CATcon.?


if you have spark when it dies, having can of instant start or propane handy is helpful.
spark good. ,pull vac hose to plenum, with can of start and its straw inject 2 sec blast of
this liquid into this vac. nipple.
put back hose and start, no start? ( it will)
or propane torch in hand , give the air horn a hit for 3 seconds. via air cleaner.
gotta start , or start an die.?

see.? my direction?

this will confirm if you are lossing injection. ( humm starts with instant start, hummmm)

when not starting, do you smell gas?, are the plugs wet?
it might be flooding, so try WOT , on gas pedal (unflood mode , cut fuel mode) (wot=wide open throttle)

also if the IAC does not open for starts, you can experience loss of start air.
this will flood engine. or at the least , make for hard starts.
if you suspect that , just give 5% throttle at start.
kicks will start this way with bad IAC or the ECU decided to not like it anymore.

the ECU has two more sub modes.
failsafe and backup, little is written about these 2 modes.
but this is used when ECU can not control the engine anymore, and it drops to these, modes.
Backup is the dumbest mode. and does not have idle controls.

open ecu. (behind left front speaker)
remove corner capactor , next to main connector. put in a new cap , observing polarity.
look for leaking caps,
clean any leaks with bicarb/water mix with a q-tip stick. neautralize any leaks.
leaks ,eat the copper traces.
jumper any , eaten traces.

all above assumes, good fuel pressure. and Fuel pressure reg.

cheers.

tell what head you have please.?