Riddle for the renix masters........
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Riddle for the renix masters........
89 4.0 200k. I have replaced almost everything in this rebuild, All along I've had hot no start. From now on that's "HNS". It's now in the dictionary.
A list of what's been done. Remember, the HNS was happening BEFORE this process began.(June 2012) It continues to this day. Restart immediately no problem. Wait 10 minutes might as well wait until it completely cools down.
Battery, new 4 gauge for grounds at negative terminal & firewall & dipstick bolt(per Cruisers notes) plugs(champion copper), wires, dizzy, coil, ICM, TPS, MAP, IAC, MOPAR CPS(adjusted per Cruisers notice) Fuel Reg, Bosch Inj. , Front & rear harnesses, ballast resistor, super cleaned throttle body, super cleaned ALL electrical connectors MULTIPLE TIMES.
Today I unplugged the dizzy & drove it 4 miles. Shut it off & waited 6 minutes. HNS. The PO put a AT fuel pump in it. It's getting louder. I have 39 & 31 at the rail hot or cold. The only chance of it starting is if I LIGHTLY press the foot feed as I crank. If it happens to start it's a ruff mother *^#@(&%. Then it will slowly smooth out. Gas mileage is terrible.
I suppose this is some kind of thermal failure. The warmer the weather the worse the HNS is.
We were gonna use some dynamite tomorrow afternoon to remove some stumps in a pond I'm building. She may get parked on one. So if you hear a "pop" ........it probably ain't a beer top.
A list of what's been done. Remember, the HNS was happening BEFORE this process began.(June 2012) It continues to this day. Restart immediately no problem. Wait 10 minutes might as well wait until it completely cools down.
Battery, new 4 gauge for grounds at negative terminal & firewall & dipstick bolt(per Cruisers notes) plugs(champion copper), wires, dizzy, coil, ICM, TPS, MAP, IAC, MOPAR CPS(adjusted per Cruisers notice) Fuel Reg, Bosch Inj. , Front & rear harnesses, ballast resistor, super cleaned throttle body, super cleaned ALL electrical connectors MULTIPLE TIMES.
Today I unplugged the dizzy & drove it 4 miles. Shut it off & waited 6 minutes. HNS. The PO put a AT fuel pump in it. It's getting louder. I have 39 & 31 at the rail hot or cold. The only chance of it starting is if I LIGHTLY press the foot feed as I crank. If it happens to start it's a ruff mother *^#@(&%. Then it will slowly smooth out. Gas mileage is terrible.
I suppose this is some kind of thermal failure. The warmer the weather the worse the HNS is.
We were gonna use some dynamite tomorrow afternoon to remove some stumps in a pond I'm building. She may get parked on one. So if you hear a "pop" ........it probably ain't a beer top.
#2
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Year: 1998
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I know squat about Renix, but I wonder how big of a part the coolant temp sensor plays in the fuel mapping. Also, do they have an intake air temp sensor? Hopefully cruiser54 comes along soon!
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What is your fuel pressure if you kill the engine and monitor it?
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I don't honestly have a clue about air intake sensor on a renix.
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IAT has the same values as CTS. Ever cleaned it? The IAT.
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He he.......those figures are messin with my mind. I left the gauge on it (hot) & when I shut it down it was 31. Dropped what I thought was a bit too quick. It went down about 15 psi in less than 4 minutes. So I'm thinking leak down.
So I do it again & this time instead of going down when I shut it off the pressure goes up to like 50 psi. Stayed there a long time. I got tired of waiting so I was gonna bleed it off at the rail & I got at least3 to 4 ounces outta the stem. Never had to bleed that much before.
I didn't know what to think about that but I started wondering about the regulator. Stated to just jump & replace it but it's only been on there for about 400 miles & it's from NAPA.
btw when I say hot I mean normal operating temp. And speaking of temp. I have a brand new radiator in there & TS. I notice when driving sometimes the gauge will move pretty quickly from the 1st mark up to 210 then all the sudden quickly fall back to the 1st mark. Kinda goes back n forth. N ever runs hot.
So I do it again & this time instead of going down when I shut it off the pressure goes up to like 50 psi. Stayed there a long time. I got tired of waiting so I was gonna bleed it off at the rail & I got at least3 to 4 ounces outta the stem. Never had to bleed that much before.
I didn't know what to think about that but I started wondering about the regulator. Stated to just jump & replace it but it's only been on there for about 400 miles & it's from NAPA.
btw when I say hot I mean normal operating temp. And speaking of temp. I have a brand new radiator in there & TS. I notice when driving sometimes the gauge will move pretty quickly from the 1st mark up to 210 then all the sudden quickly fall back to the 1st mark. Kinda goes back n forth. N ever runs hot.
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What about those fuel numbers? Will a goofy pump/sender/regulator assembly cause a HNS?
#10
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Good luck finding an IAT. I wouldn't bother. Just use what you got. In the meantime, see how it works all cleaned up.
I can't see a fuel pump/sender causing a HNS. Have you actually monitored the fuel pressure during the HNS though?
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Yea that's what's so crazy. I'll drive it 5 to 10 miles & get back to the house & pop the gauge on there. Sometimes it will drop 15 to 20 then the next time it will go up to 48 to 50 & just sit there.
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I'm not thinking it should ever sit at 50 Lbs. Maybe quick pull a plug at no-start and see if it looks flooded.
I didn't see right off if you checked CPS ac volts at no start...
I didn't see right off if you checked CPS ac volts at no start...
#13
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Can you leave it on and see if there's a correlation between the HNS and certain fuel pressure readings?
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I gotta agree with you on that. Your system shouldn't hold 50 lbs that sounds too high...here's a question : I know in 97+ if you floor the accelerator during crank it will de-flood the motor by cutting off injectors. Is this the same for renix?
#15
go to napa or if you have a harbor frieght, get a spark tester. One that goes inbetween the plug and wire. When it doesn't start, put the tester on and see if you are loosing spark. Could be the pcm. If you are getting spark, next thing to check would be to see if you are getting injector pulse, can also get an injector tester at hf, or you can wire in a light into on of the injector plugs.