will knock sensor bad prevent full throttle on 84?
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From: Mulberry Florida
will knock sensor bad prevent full throttle on 84?
Hey guys. I recently bought an 84. Have sunk a lot into it and can't solve this one problem. When I first got it it would drive but would surge when idling and eventually stall. You had to two foot it at stop lights to keep from dying. I put it in the shop where they replaced injectors and replaced and rewired the knock sensor. They said it ran well but then just took a dump and they had no further solutions. So I brought it home, read on here a bit, and decided since it would be cheap to try the 85 pump. When putting it on I noticed 1) the little inch long coupler fornthr fuel pump had split. And 2). The return fuel line was completely clogged full of trash. I replaced the pump, cleaned the unit. Got a new strainer. Put it all back together and it ran wonderfully. Full throttle and all. After a very long drive it still didn't want to idle though. Would start surging. But I was happy for the time being.
But yesterday, driving in the rain, it started again where I can't give it too much gas or it bogs out. Anything past about half throttle and it stops producing power and just bogs out. The 43 knock sensor code has never went off but it has a new sensor and has been rewired. Could it have gotten wet or damaged in the rain and cause this?
But yesterday, driving in the rain, it started again where I can't give it too much gas or it bogs out. Anything past about half throttle and it stops producing power and just bogs out. The 43 knock sensor code has never went off but it has a new sensor and has been rewired. Could it have gotten wet or damaged in the rain and cause this?
Racer
Joined: Dec 2006
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From: shapleigh maine
Fuel filter? Maybe it is clogged with the same stuff? I know it is a PITA on a crossfire car, but you must know your fuel pressure numbers when the problem is occurring. Low fuel pressure equals poor performance.
Bob
Bob
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From: Mulberry Florida
But the knock sensor wouldn't cause this? Its the only bad code its had since I've had it.
Drifting
Joined: Mar 2009
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From: East Wenatchee (2hours from n e where) WA
You can get a knock code when it leans out. When the computer sees the knock sensor trigger it pulls timeing out. sounds to me like you have a bunch of trash in the fuel system. btw that shop sounds like a real POS. "We threw some parts at your car, it aint fixed, heres the bill!"
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From: Mulberry Florida
You can get a knock code when it leans out. When the computer sees the knock sensor trigger it pulls timeing out. sounds to me like you have a bunch of trash in the fuel system. btw that shop sounds like a real POS. "We threw some parts at your car, it aint fixed, heres the bill!"
They replaced regulators and injectors. If in change the filter and clean the tank should I be good? Or could they be trashed up already?
Drifting
Joined: Mar 2006
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From: Wabasha Mn
Hook a fuel pressure gauge to the fuel line down near the passenger side frame where the inline fuel filter is mounted. Check pressure before and after the filter and see what kind of pressure drop you have, if any. If you have good pressure there your problem is probably with the pressure to the tbi's, too much or too little.
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From: Mulberry Florida
Thanks for all the help guys. I ordered for $89.95 this fuel rail attachment with a gauge built in, from a Crossfire enthusiast company. Going to install it to get pressure between the throttle bodies(i think, maybe just after the regulator? IDK) Also saw where people put a visible on by the sending unit. Going to put one there too.
But it seems for the time being Blackbearbob was right, I put a new fuel filter on and the one that was on it, maybe a couple weeks old, was nasty, looked like mississippi mud pouring out the one end, but the other end was clear and the line running to the filter was running clear by that time too. I also put an MSD cap and rotor on it, but seeing as how it was running fine until it took a dump, I figure that dump was more likely the clogged fuel line than some timing problem, I still didn't adjust it at all.
Again, thanks for all the tips, I am super glad I joined this forum! I'll get some gauges before asking any more tuning questions
But it seems for the time being Blackbearbob was right, I put a new fuel filter on and the one that was on it, maybe a couple weeks old, was nasty, looked like mississippi mud pouring out the one end, but the other end was clear and the line running to the filter was running clear by that time too. I also put an MSD cap and rotor on it, but seeing as how it was running fine until it took a dump, I figure that dump was more likely the clogged fuel line than some timing problem, I still didn't adjust it at all.
Again, thanks for all the tips, I am super glad I joined this forum! I'll get some gauges before asking any more tuning questions
Drifting
Joined: Mar 2009
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From: East Wenatchee (2hours from n e where) WA
Sounds like your goin in the right direction. I would take that pluged filter back to the shop and show them what their 1700$ fuel system cleaning looks like. I would think about 1500$ back would be fair. Is this an ASE certified shop? There will probly be a lot more trash to clean out. There should be a strainer on the pump that will need cleanup.
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From: Mulberry Florida
Sounds like your goin in the right direction. I would take that pluged filter back to the shop and show them what their 1700$ fuel system cleaning looks like. I would think about 1500$ back would be fair. Is this an ASE certified shop? There will probly be a lot more trash to clean out. There should be a strainer on the pump that will need cleanup.
Not sure if I can name names here but it was Tires Plus, they are supposed to be ASE certified, they would tell me they knew what was wrong, do it, then tell me that didn't fix it. I thought about contacting the BBB.