Will not start under 45 degrees
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Will not start under 45 degrees
I have a 91 Ranger 4cyl. Tune up about 2 months ago. Mileage about 178,000.
When the tempature gets below about 45 degrees, the truck will not start. It cranks like the battery has plenty of juice but refuses to start. Once the temp warms up, the truck will start first crank. No one seems to have any idea why.
When the tempature gets below about 45 degrees, the truck will not start. It cranks like the battery has plenty of juice but refuses to start. Once the temp warms up, the truck will start first crank. No one seems to have any idea why.
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Joined: Jan 2004
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From: SW Va
^+1 on hooking up a scantool to have a look at things & post up All trouble code Numbers found when you scan the computer for trouble code clues.
Takes compression, air, fuel & spark to make en run, so when its in one of its no start fits, whats going missing???? Use your ear to listen for the fuel pump to run at KOEO for a couple of seconds & turn off, before you crank the engine. Use your fuel pressure gauge to measure fuel pressure at the under hood fuel rail schrader valve test port & post the pressure numbers. Use your inductive timing light to safely check for spark when you crank the engine & let us know what you find.
Takes compression, air, fuel & spark to make en run, so when its in one of its no start fits, whats going missing???? Use your ear to listen for the fuel pump to run at KOEO for a couple of seconds & turn off, before you crank the engine. Use your fuel pressure gauge to measure fuel pressure at the under hood fuel rail schrader valve test port & post the pressure numbers. Use your inductive timing light to safely check for spark when you crank the engine & let us know what you find.
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I have taken it to a mechanic shop I have used before. They have had it for a week. Said they could not duplicate the problem. They called yesterday and told me the relay had an intermittent short that was causing the fuel pump not to work. Said they would have to replace the fuel pump, sensor and relay. Told me it was going to cost about a thousand bucks. Told them I would have to think about it. They called me back about an hour later and told me they gave me the wrong price and it was only going to be about $550. I get the idea that they really do not know what the problem is and are just throwing parts on in hope that it fixes it. Does it sound like that to you guys?
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Joined: Jan 2004
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From: SW Va
Kinda sounds like their guessing, while using your money. Ask them what trouble code Numbers they got when they scanned the computer, that caused them to think those things were faulty.
When it would act out & not start, could you hear the fuel pump run for a couple of seconds to prime the system, then cut off??? Or was the fuel pump silent when you'd go to KOEO, before cranking the engine???? The fuel pump power relay is a common problem part & if suspected, can be swapped out for a like power relay not needed to run the engine, like the A/C power relay, located in the under hood power distribution fuse/relay box, & if that fixes the problem, you'll know it was the fuel pump power relay & this only takes a couple of minutes to do yourself & a replacement relay is only about $6 at the parts store.
Ask them what they measured for fuel pressure at the fuel rail schrader valve test port, that caused them to suspect a failing fuel pump.
BTW, what "sensor" were they talking about replacing????
When it would act out & not start, could you hear the fuel pump run for a couple of seconds to prime the system, then cut off??? Or was the fuel pump silent when you'd go to KOEO, before cranking the engine???? The fuel pump power relay is a common problem part & if suspected, can be swapped out for a like power relay not needed to run the engine, like the A/C power relay, located in the under hood power distribution fuse/relay box, & if that fixes the problem, you'll know it was the fuel pump power relay & this only takes a couple of minutes to do yourself & a replacement relay is only about $6 at the parts store.
Ask them what they measured for fuel pressure at the fuel rail schrader valve test port, that caused them to suspect a failing fuel pump.
BTW, what "sensor" were they talking about replacing????
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bdonalds
1987 - 1996 F150 & Larger F-Series Trucks
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Apr 4, 2001 02:16 PM
