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98 firebird runs hot,oil pressure drops?


debbi57
06-24-2011, 12:51 PM
Hi I bought a 98 Pontiac Firebird V6 and its got me:runaround:The temp gauge goes to the 1/2 mark (210),then the oil gauge drops to the 1/4/mark and goies between 1/4 and 1/2.Then my "service engine soon" light comes on. I put code reader on & it reads EGR on closed. I've put a new radiator & thermostat in & its still does the same:shakehead Can anyone help me out here with some ideas? :confused: I work on my own car & most of the guys I know havent worked on a car older than a 1990 Thanks, Debbi57

MT-2500
06-25-2011, 04:40 PM
Hi I bought a 98 Pontiac Firebird V6 and its got me:runaround:The temp gauge goes to the 1/2 mark (210),then the oil gauge drops to the 1/4/mark and goies between 1/4 and 1/2.Then my "service engine soon" light comes on. I put code reader on & it reads EGR on closed. I've put a new radiator & thermostat in & its still does the same:shakehead Can anyone help me out here with some ideas? :confused: I work on my own car & most of the guys I know havent worked on a car older than a 1990 Thanks, Debbi57

What was code no?
Egr valve does not affect oil pressure.

210 is a little warm.
But on some cars the cooling fan does not kick in untill over that?
And temp gauges can be off just like oil pressure gauges can be off.
Wher does your fan kick in with ac off?
And do fans work all time with ac on?
MAKE SURE TEMPT GAUGE IS WORING RIGHT.
Is that 210 sitting still without ac on or ac on or driving down the road?
If it has electric rad fan/fans?
Is the rad fans working right?
How hot does it get running down road?
Does it get that hot with AC on?

On the oil pressure you need to check oil pressure with a manual test gauge.
As with temp gauge make sure oil pressure gauge is working right,

debbi57
07-01-2011, 05:48 AM
Hi Thanks for the reply.Sorry took me so long to get back.Not sure when fan kicks in(dont hear good so I have to use vibrations to help me with that)but it is on when its 210 with or without ac.Dont use ac since it needs serviced.Will see about getting that done today.When car is idling or on freeway it takes a little longer to reach 210 but I can go from Auburn Blvd to El Camino amd its already 210. The EGR code was P 0404 EGR in closed postion.Last night another code showed up P1870- The Freeze Frame shows what rhe car is reading now.Do you know where I can find out what it is suppose to read? Thanks Again....debbi

MT-2500
07-01-2011, 06:48 AM
Hi Thanks for the reply.Sorry took me so long to get back.Not sure when fan kicks in(dont hear good so I have to use vibrations to help me with that)but it is on when its 210 with or without ac.Dont use ac since it needs serviced.Will see about getting that done today.When car is idling or on freeway it takes a little longer to reach 210 but I can go from Auburn Blvd to El Camino amd its already 210. The EGR code was P 0404 EGR in closed postion.Last night another code showed up P1870- The Freeze Frame shows what rhe car is reading now.Do you know where I can find out what it is suppose to read? Thanks Again....debbi

You have several problems.
Worst one is P1870 transmission code.
It is showing a componet sliping.
You need a transmission capable scanner to show what gear or TCC is sliping and how much slipage.
Usualy slipage is interal transmission trouble/problems.
Is the fluid low or burnt or filter stopped up?
Has transmission ever been serviced?
Code P0404 is the egr pintel position does match with actual and disered position.
in freeze frames or running frames check actual erg position with desired position.
If over 15 % differance it sets code.
You may have a bad EGR valve.

On high tempt and oil pressure droping.
You need to run a oil pressure test with a manual oil pressure testgauge.
Check for oil pressure gauge readng matching manual oil pressure test gauge.
If not matching try a new oil pressure sending unit.

On high tempt problem when AC is not working the car will heat up to 210 or more before it turns on cooling fan.

With AC working the coling fans run when AC or defrost is on all of the time helping to keep engine runnng tempt at thermostaff tempt. around 195-200.

Also going down road at 40-50-65 MPH the air blowing trew rad should hold tempt down to 195-200.

What is you tempt running at 50-65 MPH?

debbi57
07-06-2011, 03:38 AM
Hi Thought I'd let you know I got the codes fixed.Cleaned the EGR & changed the tranny fluid.Dont think its ever been changed before. Ive never done a oil pressure chek before...Got a engine pressure kit but the instructios doesnt hace Pontiac in it.so Im going to call the number thats in the instructions tomorrow. Thanks again for helping me out. Deb

MT-2500
07-06-2011, 06:03 AM
Hi Thought I'd let you know I got the codes fixed.Cleaned the EGR & changed the tranny fluid.Dont think its ever been changed before. Ive never done a oil pressure chek before...Got a engine pressure kit but the instructios doesnt hace Pontiac in it.so Im going to call the number thats in the instructions tomorrow. Thanks again for helping me out. Deb

You are welcome.
Checking a pomatic should be the same as other brands. only difference may be where to hook up gauge.
Just find where the oil pressure sening unit goes to engine and take it from there.
Hook the manual gauge to the oil pressure hole where the electric sending unit goes to engine.
I always like to T the electric sending unit in with the manual gauge if room and fittings permit.
That way you can match the electric dash gauge reading with the manual gauge.
Good Luck and let us know how it goes

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