Tech / General EngineWhy is my car making that sound? My car won't start! Combination questions? Don't see a board for your problem or have other technical or engine specific questions? Post them here!
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I have a 87 305 TPI (ran good for last 3 years)... About a week ago it started hesitating real bad right @ 1500 rpm in all gears (sometimes even backfire), would bog out for a few seconds and once it got to 1700 and up it would be fine. Also startup and idle was good.
Last night it started idleing poorly and ran terrible up until 1700-2000 rpm, then ran "ok" (noticible power loss though). Today I changed plugs, wires, cap, rotor, coil, and fuel filter. Checked for vacuum leaks (and gauge read good, around 20"), timing is on, and EGR appears to be ok. Still running terrible, rough idle, very bad hesitation up to 2000 rpm, and still noticible power loss 2000-up.
Reading through many posts, the next things I should check would be TPS, IAC, and MAF (and relay?). I also got a fuel pressure reading of 30 which i know is very low but the gauge leaked so I don't know how accurate that was yet. Whatever happened, it happened over the course of a few times driving the car. If anyone has any suggestions, it would be greatly appreciated!
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I have a 87 305 TPI (ran good for last 3 years)... About a week ago it started hesitating real bad right @ 1500 rpm in all gears (sometimes even backfire), would bog out for a few seconds and once it got to 1700 and up it would be fine. Also startup and idle was good.
Last night it started idleing poorly and ran terrible up until 1700-2000 rpm, then ran "ok" (noticible power loss though). Today I changed plugs, wires, cap, rotor, coil, and fuel filter. Checked for vacuum leaks (and gauge read good, around 20"), timing is on, and EGR appears to be ok. Still running terrible, rough idle, very bad hesitation up to 2000 rpm, and still noticible power loss 2000-up.
Reading through many posts, the next things I should check would be TPS, IAC, and MAF (and relay?). I also got a fuel pressure reading of 30 which i know is very low but the gauge leaked so I don't know how accurate that was yet. Whatever happened, it happened over the course of a few times driving the car. If anyone has any suggestions, it would be greatly appreciated!
use some sensor safe cleaner on your MAF, run some seafoam through the tank and through the top end just to get some carbon out.
i would check O2 sensors, IAC, and MAF, for sure, in that order. the O2 sensors could easily cause those symptoms by causing a false lean or rich condition, the IAC motor could be causing the rough idle as well as a vacuum leak. the MAF is closely related to the O2's so that could cause lean/rich condition as well as the resulting backfiring.
are you sure your timing is dead on? that could be a simple solution. not a tooth off on the dizzy, etc.?
I forgot to mention I did use the cleaner on the MAF and replaced the O2 sensor. Is there a way to check the IAC? other than buying a new one? The timing reads 8* BTDC, when the idle finally calms down.
It has it's moments. It will hold steady for a while, then run rough... back and forth (in park). However, when in drive the idle will not hold steady. It idled fine a week ago when the problem @ 1500 RPM started. I drove it twice since everything got real bad, to and from the garage i'm using to work on it. It actually ran better when it was cold and became worse as it got up to temp
I put on a new MAF with no change. Then I checked the fuel pressure and found the problem. I was only getting 25-30 PSI and the car was barely running. Changed out the pump which was quite a job. I had bought a new TPS and IAC so I put those in as well and set everything correctly. The car has never ran so good since I have owned!!!
The only "problem" is the fuel pump does not prime for 2 sec when ignition on. It only starts pumping when cranking and obviously when it is running. I can hear the relay kick on for the 2 sec but the pump does nothing.
Given all I have been through with this car lately, I can deal with this...
