89 4.0 engine / computer ground locations?

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badgator

NAXJA Forum User

Location

Roaming the swamps

• Jan 28, 2006

• #1

Does anyone know all the ground locations for my 89 cherokee, I just bought it for work and idles rough / rich, low power, I changed the spark plugs and wires checked cap and rotor already. It really sux I can't pull the computer codes myself.

 

mingo

"De Oppresso Liber"

Location

Layton, UT / Frutia, CO

• Jan 28, 2006

• #2

Two grounds that I know of, one behind the valve cover going to the firewall. Small braided crappy cable. The other is on the engine block on the right side (passenger). Sounds more like a vaccum leak to me. Check the vaccum line going to the MAP sensor. Its the little hard plastic line coming out of the TB to a sensor thats mounted on the fire wall close to above mentioned ground.

 

B

badgator

NAXJA Forum User

Location

Roaming the swamps

• Jan 28, 2006

• #3

I checked the vacuum lines as the previous owner had the engine replaced and the rounting was wrong, apparently HO motor, does the map sensor go the the upper or lower tb port, mine has two.

 

langer1

NAXJA Forum User

Location

Mineral City,Ohio

• Jan 28, 2006

• #4

badgator said:

I checked the vacuum lines as the previous owner had the engine replaced and the rounting was wrong, apparently HO motor, does the map sensor go the the upper or lower tb port, mine has two.

Click to expand...

Bottom hole top is plugged.

 

mingo

"De Oppresso Liber"

Location

Layton, UT / Frutia, CO

• Jan 28, 2006

• #5

I want to say the bottom one, but not quite sure without going outside to look. If I remember there should be a small rubber plug that the line slips into the back of the TB. And they were different sizes. I'm sure someone else will chime in that know exactly what goes where.

 

B

badgator

NAXJA Forum User

Location

Roaming the swamps

• Jan 28, 2006

• #6

Map sensor goes into lower hole upper blocked off, found out while cleaning tb and idle air valve. Still runs like crap, one fuel injector did'nt work at all, replaced, runs a litttle better.

 

mingo

"De Oppresso Liber"

Location

Layton, UT / Frutia, CO

• Jan 28, 2006

• #7

Might look at the oxygen sensor also. Could be sending bad info or no info out to the ECU.