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Hey there enthusiasts! I am new to the forum and a proud owner of a 1988 Fox body LX 302 5.0.

I recently purchased this car from a friend who I knew back from high school and he has done a few things.

New crate motor (only block and head) only has 40k miles on it. Rest is from previous motor.

Has a full BBK 3 inch exhaust from headers to h pipe to flowmaster 40's.

Other than that the car is 100% stock.

The car runs and drives fine once warm. However, before I bought it I knew it was going to have a few issues since it had been sitting a while. When you turn the key everything sounds fine then when the car starts the rpms fluctuate. starting from around 800 and then dropping down to almost 200 before it kicks back up to 800rpms. The car shudders and feels like it wants to stall. Some times it does, sometimes it doesnt. I find myself most of the time holding the gas pedal at 1000 rpms until I finally decide to put it in gear and take off. Once the car is warmed up I can drive around town, hit every red light, and it wont stall. But the minute I shut the car off and start it back up again it does the same thing. Even if the car is already warmed up.

For example, I went and got gas. Started the car at my house had idle issues. Drove through town hit every red light and idle was normal around 6-700 RPMs. Then I got to the gas station shut it off. Filled her up turned her back on about 5 mins later and she wants to stall again. I also notice that my oil pressure is on the "L" out of the "normal" written in the gauge. I notice when the car is at idle standing still the oil pressure drops to near off the gauge. When the car is moving the guage goes back to the "L".

Having said all of that. I have a couple questions.

1.) What do you think is causing it to want to stall at initial start up? (even after its warmed up)
2.) What is the normal average running level of oil pressure that my car should be running at when driving and at idle? Should it be the same? Is "L" too low?
3.) What could be causing my oil pressure to constantly fluctuate?
4.) The last issue is related to the automatic transmission. I recently had the the joint replaced the calibrates when the transmission shifts. I was told it needs to be recalibrated since it has a new joint. I'm finding that the car shifts so early into the next gear that the gas pedal almost feels like it has a "dead spot". I just want to double check that this is only because the joint needs to be recalibrated.

I am taking the car to stage one performance in NJ, but wanted to know what to expect before bringing it in.

Any knowledge or advice is greatly appreciated to this newcomer to the forum and mustang life!
 

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1) Possible dirty iac valve (cylinder part that is attached to the throttle body), clean it or replace it. Or possible Vacuum Leak

2) Get you a real gauge like an autometer, factory gauges are not very accurate. Rule of thumb is 1 psi of pressure per 100 rpm.

3)Oil pressure should fluctuate based on rpm. As long as you are within the minimum as I mention above, your motor will be fine.

4) Sounds like your throttle pressure cable needs some adjustment or needs to be replace. Check out this short clip: Ford AOD TV cable adjustment - YouTube

Hope this helps

Hey there enthusiasts! I am new to the forum and a proud owner of a 1988 Fox body LX 302 5.0.

I recently purchased this car from a friend who I knew back from high school and he has done a few things.

New crate motor (only block and head) only has 40k miles on it. Rest is from previous motor.

Has a full BBK 3 inch exhaust from headers to h pipe to flowmaster 40's.

Other than that the car is 100% stock.

The car runs and drives fine once warm. However, before I bought it I knew it was going to have a few issues since it had been sitting a while. When you turn the key everything sounds fine then when the car starts the rpms fluctuate. starting from around 800 and then dropping down to almost 200 before it kicks back up to 800rpms. The car shudders and feels like it wants to stall. Some times it does, sometimes it doesnt. I find myself most of the time holding the gas pedal at 1000 rpms until I finally decide to put it in gear and take off. Once the car is warmed up I can drive around town, hit every red light, and it wont stall. But the minute I shut the car off and start it back up again it does the same thing. Even if the car is already warmed up.

For example, I went and got gas. Started the car at my house had idle issues. Drove through town hit every red light and idle was normal around 6-700 RPMs. Then I got to the gas station shut it off. Filled her up turned her back on about 5 mins later and she wants to stall again. I also notice that my oil pressure is on the "L" out of the "normal" written in the gauge. I notice when the car is at idle standing still the oil pressure drops to near off the gauge. When the car is moving the guage goes back to the "L".

Having said all of that. I have a couple questions.

1.) What do you think is causing it to want to stall at initial start up? (even after its warmed up)
2.) What is the normal average running level of oil pressure that my car should be running at when driving and at idle? Should it be the same? Is "L" too low?
3.) What could be causing my oil pressure to constantly fluctuate?
4.) The last issue is related to the automatic transmission. I recently had the the joint replaced the calibrates when the transmission shifts. I was told it needs to be recalibrated since it has a new joint. I'm finding that the car shifts so early into the next gear that the gas pedal almost feels like it has a "dead spot". I just want to double check that this is only because the joint needs to be recalibrated.

I am taking the car to stage one performance in NJ, but wanted to know what to expect before bringing it in.

Any knowledge or advice is greatly appreciated to this newcomer to the forum and mustang life!
 
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