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Discussion Starter · #1 ·
93 Fleetwood 5.7 Tbi.

So I've had this car about 2 years and haven't put 1k on it since I've had it. Odometer said 190k. Only drivin it from shop to the house painting, interior, etc. And it hasn't givin me any problems untill on the way home a few months ago. It blew the head gasket between #4 and 6 cylinder. The block had high compression so I tore it down to the block and replaced the heads(all stock nothing proformance on whole motor), intake, timing chain, lifters, push rods, rollers, distributor, icm, cap, rotor, plugs, wire's, coil, egr, egr valve solenoid, pvc, all vaccum lines, cts, water pump, thermostat, I believe thats it. All new grounds, power wire to fuse box under hood new.

I finally get the motor all back together, set the timing and adjust the rollers and the car's had a pretty bad miss at idle. Like it's stuggling to stay running. Rev it up and it sounds wonderful, rev it a little over idle and its fine. Only @ idle there is a miss. If you throw it in gear it will die. It stayed running better before the valves were fully adjust and the timing set dead on. There was a cel on and we scanned it, came back as a bad CTS so I changed that and it would idle better. I dont have the temp switch in the drivers head hooked up. I'm under the assumption that thats only for the dummy light on the dash, but I could be a dummy and that temp switch needs to be hooked up. The connector is broken on it and thats the only reason I didnt plug it up. Fuel looks to be spray normal from the injectors. After the motor was running for a while with the scan tool on it I started to hear a noise comming from the TB that sounded like a really loud vaccum leak but it's not I went over all the lines. So I have no clue on that noise. I have no clue of what the problem could be. Hopefully I didn't leave anything out.

Thanks for any help. I'm ready to get this car on the road.
 

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Well, it's not the temp sender. I haven't hooked mine back up yet and the car runs fine(even with open headers). The spotty idle and phantom vac leak is exactly the same thing my Ram does periodically, but I have yet to take the time to diagnose it. I suspect it's a bad/dirty IAC but not sure...
 

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Did you try puting a timing light on each plug wire at idle to check for spark on each wire?

Try shining the timing light on the injector spray pattern, or use a noid light to check for missed pulses to the injectors.

Have you removed the plugs to read them...a miss should show up on a plug as an incorrect color. If one is different, at least you know which cylinder is the culprit.
 

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Discussion Starter · #4 ·
No I didn't try what you said with the timing light but I will tomorrow. And I put a fresh set of plugs in this morning. All the other plugs were black from when the CTS was bad and not burning the fuel. So new plugs and new CTS this morning and it was alot better but still running ruff at idle.
 

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Did you squirt some water with a little detergent in it on all of the vacuum lines, and where any intake parts join?
 

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Discussion Starter · #6 ·
No I haven't heard of that. What would I be looking for? I'm not a mechanic by trade, I do custom audio, paint and body work. I have the build down just not the lil tricks. So thanks for any help, I;m down to try anything. Going to work on it first thing this morning. But all vaccum lines, all hoses, etc are new. But I will try what your saying.
 

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If there is a leak, the vacuum will suck the water up. Having new everything does not mean that there are no issues.

You could also get a stethescope and listen for the cylinder that is misfiring.

It would be helpful if we knew whether it is a global problem, or only affects a single cylinder.

Did you check for even cylinder pressure since you reassembled the engine?
 

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Discussion Starter · #8 ·
Well I knew it had something to do with setting the timing and adjust the roller's as it was running fine before that was done. I have never adjust the roller's myself before or paid attention while someone was doing it as to why I took it to a mechanic to have it done. And the "mechanic" had the roller's to tight making the car run like ****. So I had a friend adjust them and showed me how to do it. Now the car run's fine. So I just wasted alot of time and money but i will know next time what to do. Guess ya live and learn.

Thanks for all the help and response's.
 

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an easy way to check for a vacum leak is grab a torch oxy/acc or propane. open the valve to let the gas flow (don't light it), and go around anywhere there could be a leak. if you find a leak you'll notice the idle will smooth out a bit and it'll raise the idle.

by the way that fleetwood looks badass!!!!!
 

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Discussion Starter · #10 ·
an easy way to check for a vacum leak is grab a torch oxy/acc or propane. open the valve to let the gas flow (don't light it), and go around anywhere there could be a leak. if you find a leak you'll notice the idle will smooth out a bit and it'll raise the idle.

by the way that fleetwood looks badass!!!!!
Already thanks.
 
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