02-22-2008, 08:49 AM
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87 milano will not rev over 3k rpm when cold?
The like title says, if I get in the car and start driving, if I try to rev it over 3k rpm (the tach reading), it starts missing and shaking really bad and will not rev any higher. I only started doing this a few days ago, and it is wet and rainy here right now, so I imagine that has something to do with it. Any ideas of what areas I should check for loose/corroded connections, etc that would cause something like this?
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02-22-2008, 09:45 AM
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And you are sure it is not your tach that is showing too low, and in reality you are bouncing off the rev limiter? The tachs are prone to failure, showing too low...
Jes
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02-22-2008, 09:56 AM
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+1
the tachs have a history of reading low. Find someone with a timing light that has a rpm readout as well; better yet, borrow it for when the day is damp (i.e. reproduce the conditions) then verify that the car's tachometer agrees with the other measuring device (in this case, the timing light with the rpm readout)
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02-22-2008, 09:57 AM
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When the car is warm, it will rev past 5k on the tach without any problem. It does feel like hitting a rev limiter, but it stops doing it after driving for a few minutes when the car starts to get warm.
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02-22-2008, 10:02 AM
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some multi meters have that function too, don't know if you have to pay 430gbp like i did tho
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02-22-2008, 01:49 PM
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I'd be looking for condensation/moisture getting into the ignition system some where. Check all your plug leads and distributor cap.
Also, may be a dodgey coolant temp. sensor. Computer doesn't know engine is cold, engine runs like crap until it gets some heat into it. Maybe  .
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02-22-2008, 01:55 PM
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theres also another sender on the stat housing which was prone to play up, and as a consiquence Alfa themselves say to disconnect it (housings with 3 senders only)
this is a mod that should have been carried out at a time when these cars were still current. nearly 20 years down the line, i did mine!
one sender is for gauge, 2 for ecu, only one needed
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02-22-2008, 03:13 PM
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This seems worse than a coolant temp sensor, but I will check that. I drove it to school today and it ran like crap most of the way there, then when I left it was dry and sunny and by the time I got home it would rev to 5500 rpm no problem, when before it would start missing really bad at around 3000 and 4500 (the reading on the tach). In the past, I know it would rev to 5500 rpm on the tach without hitting the rev limiter (although I rarely rev it that high).
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02-22-2008, 03:28 PM
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 Quote:
Originally Posted by alfaspence
theres also another sender on the stat housing which was prone to play up, and as a consiquence Alfa themselves say to disconnect it (housings with 3 senders only)
this is a mod that should have been carried out at a time when these cars were still current. nearly 20 years down the line, i did mine!
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Although when mine was still connected, even though it caused horrible cold starts, I could still get to 6300rpm if I so desired.
I'd be thinking it has something to do with the moisture and ignition breakdown as Duk has suggested. My car also used to have issues during really heavy downpours, but it's since stopped (probably because it had never seen heavy rain before up here!  )
ROCK ON
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02-22-2008, 03:54 PM
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I'm sorry this is not going to be much help, and you need to fix it anyway......but it's not a bad thing not to rev over 3000 rpm when cold
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02-22-2008, 03:58 PM
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Quote:
Originally Posted by Peter
I'm sorry this is not going to be much help, and you need to fix it anyway......but it's not a bad thing not to rev over 3000 rpm when cold |
Travis you should NEVER, EVER rev an engine when it is COLD!!!!!! Why?, because the oil is not thinned and thus cannot get everywhere quickly, also parts take a while to expand to their correct size. You also are endanger of causing oil leaks as the oil pressure will be sky high ... guaranteed you will run a main bearing if you keep this up.
3000 is my limit when a car engine is cold. With my m/c I do try to keep below 4000 for the first few miles but it is air cooled so I don't really know when it is good to get on it.
I suspect that Alfa Romeo have built in a rev limiter when the engine is cold. Good on them. Sorry if my post comes across blunt or rude, but somebody has to guide you on proper driving techniques to look after your wonderful car.
Pete
Last edited by PSk; 02-22-2008 at 04:05 PM.
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02-22-2008, 06:22 PM
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I dont think shifting at 3000 rpm after you have been driving for a 2-3 minutes is going to hurt any car? I normally drive about 25 mph in 3rd gear for the first few minutes after I leave my house, the problem I described is not right after I got in the car and started driving it, it still does it even after the car starts to get warm.
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02-22-2008, 07:26 PM
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Quote:
Originally Posted by Travis_k
I dont think shifting at 3000 rpm after you have been driving for a 2-3 minutes is going to hurt any car? I normally drive about 25 mph in 3rd gear for the first few minutes after I leave my house, the problem I described is not right after I got in the car and started driving it, it still does it even after the car starts to get warm.
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 . Cold = cold, and in the motoring sense means just started, so I panicked.
I won't be revving my Alfa, once finished, over 3000 rpm until fully warmed up, but yes this sounds like a wiring issue.
Best
Pete
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02-22-2008, 07:39 PM
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I am almost certain this is caused by a bad connection because of the wet weather. Im not sure how long it had been doing it for actually, becasue for a week all I had done was drive it to work and I didnt rev it past 3000 rpm at all most of the time. The problem seems to be when the temp is in about the middle 1/2 of the gauge, if thats a better description. Once it is up to the normal operating temp it would do the same thing but at 4500.
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02-22-2008, 10:58 PM
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Quote:
Originally Posted by Rookie ROX
Single wire, usually purple and white.
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personally if water seems to be a contributing factor, i would start by removing all plugs/connectors one by one and spraying them with a good contact cleaner...
Also check that no water is getting into the cabin around the ecu! (bulkhead is prone to rust around heater inlet and behind bonnet hinges)
just to eliminate it, check the distributor cap and leads (and that no water is getting into spark plug holes)
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