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Discussion Starter · #1 ·
I think I'm finally hot on the trail of my cold starting problems! My cold start injector sprays nicely when energized with 12v directly. Hooking a test light up to the Bosch connector lights up when it should, but...when I put the Bosch connector on the CSI and try nothing comes out.

At first I thought maybe the connector pin receptacles were mucked up and that since my test light had fatter probes that they made connections where the CSI pins didn't.

That's not the case though, I finally put a volt meter on the connector and it is only getting around 6-8 volts, I'm assuming that the injector needs 12v to open although I can't find that info anywhere but it fires fine when connected directly to the battery so that must be the case.

The question I have is how to figure out why it only has 8v coming to it. I traced one of the CSI wires to the combi-relay connector and the resistance is zero so that side seems good. There is a blue wire for the other pin in the CSI and I can't figure out where that goes to, anyone know?

Also the service manual says to check the combi relay connector for 12v from 88z and 88b with the ignition switched on. 88z has 12v and 88b has nothing, I assume by ignition on they just mean in the on position and not with the car running... If so then this could be the prob or part of it. Are these two relays interconnected? I assume so since they are one unit. Any ideas?

Thanks,
Kevin
 

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Kevin, I was under the impression that the CSI was only energized when the key was in the cranking position and when the key was returned to the run position the CSI was de-energized. At this point the coolant temp sensor is sending a "cold start" condition to the ecu which in turn broadened the pulse time on the injectors/along with the air valve gave the enriched high idle. I needed a 3rd hand to crank it while I tested the CSI. Joe btw, I had great fun in Boston, next time we'll have to get the guys together for a bite and some drinks:) I'll have photos just as soon as I can find the film, gotta go digital!
 

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Discussion Starter · #3 ·
Joe, I had fun too! Was good seeing you again.

Yes the CSI is only on when cranking but the Service manual seems to say that that post is on when the ignition is on. I was assuming that it was hot and that the relay cause the circuit to close. Could be wrong though. Doesn't really explain why full voltage is not getting through.

Kevin
 

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Assuming that the Milano L-Jet is similar to the Spider version, the CSI will electrically work when A) the starter is engaged AND B) the thermotime switch (TTS) is closed. The TTS should be closed when the coolant temp is about 35C and below. Above that, it is open to prevent the CSI from spraying fuel which could flood a warm/hot engine when starting. In addition, there is a heating element in the TTS that will open the CSI circuit after the starter is cranked for about six seconds. This too is the prevent flooding the engine. You might want to try bypassing the TTS and see if the CSI works. Just jumper the two wires in the TTS connector. The TTS is the sensor in the thermostat housing that points to the rightside of the vehicle.
 

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Discussion Starter · #5 ·
Yes, that is how it works (the same), the problem here is all the sensors and the CSI itself work fine but for some reason the voltage coming through the wire appears to be too low (around 8v) to activate the CSI. I'm trying to figure out where the other wire going to the CSI goes to, assuming it is the one supplying the power.

Kevin
 

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After looking at an 87 Milano diagram, the CSI is powered from the ignition switch only when in the start position. Power from the ignition switch enters the relay set at terminal #86a and goes straight through the relay (with a diode to a parallel circuit) to exit the relay at terminal #86.
If your getting only 8V at the CSI during cranking, I'd suspect a very poor electrical connection somewhere in this circuit. The CSI has three wires on it with two wires going to one terminal. One of these wires comes from terminal #86 on the relay set to power the CSI. The second wire (on the same terminal) goes to the TTS to power the bimetallic strip. The third single wire on the CSI goes to the TTS which determines whether or not to complete the CSI circuit to ground.
 

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I think that Kevin has a bad thermo time switch. A high resistance contact will cause his problems. Fake out the contact in the TTS with a jumper to ground and see if the injector works (or the car starts from cold).
Ed Prytherch, Columbia SC
88 Verde
79 Spider
74 GTV
 

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Discussion Starter · #8 ·
It appears we may have a winner, the TTS... It had all the proper ohm readings when hot & cold and seemed to be grounded OK but just would not fire the injector when cold. Had a spare from a car I parted out and swapped out yesterday and the engine started right up this morning with outside temps at about 41F.

The injector fires fine even with 8-9v coming out, it just needs to be grounded properly. The TTS is grounded through its threads into the thermostat which has a ground wire screwed to it. All that was fine so I'm not sure what the actual prob with the TTS was but replacing it seemed to fix the problem. We'll see how things go over the next week or so, hopefully it stays fixed!

Kevin
 

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It probably has bad contacts. Ohming out switch contacts can be misleading as digital VOM's push very little current to make the measurement. Industrial instruments for measuring contact resistance typically drive up to 10 amps.
Ed Prytherch
 

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good point about the digital VOM. I've found that I need to keep a fresh battery in the meter for accurate tests. Just leaving the meter on for extended periods will drain the battery. btw, Kevin, on cold start you said it was 41 deg that morning. What was the initial high idle #? Did it hold as the engine warmed or did it gradually settle down? I'm out of action now after surgery so it'll be a couple wks before I can get back to it. Interesting about the TTS resistance and the CSI firing. I'm hoping thats all it is w/ mine. Did you have to mess w/ the CAV?, clean it or adjust it? This will be interesting as my dad has offered to wrench for me and I will direct/supervise, Hmmmm:) Oh yeah, remember we talked about the surging 50rpm or so? Well I readjusted the TPS and disconnected the O2 sensor and it went away. reconnect the 02 and it returned. Midrange and upper end acceleration improved, smoother and better power. So for now that's how it is, Joe
 

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Hi Joe, it was nice to meet you in Boston!

joecautela said:
Oh yeah, remember we talked about the surging 50rpm or so? Well I readjusted the TPS and disconnected the O2 sensor and it went away. reconnect the 02 and it returned.
I'd say this is typically a sign of air leak in the intake system. Your O2 feedback is working fine and it is seeing lean/rich exhaust gas. The O2 trys to tell the ECU to compensate but the system respond is a too slow (under damped condition) so the whole thing cannot settle down and smooth out. This results in a bouncing (surging) pattern due to the ocillating lean/rich mixture.

Did you have to mess w/ the CAV?, clean it or adjust it?
You mean AAV (Auxilliary Air Valve)? This likely needs to be clean once in a while. You can test it with a heat gun, hair blower or your toaster oven to check that it opens and closes properly.

Bob C
 

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Hey Bob! I had for gotten your BB name. How's things? I did find a ruptured hose at the container up under the RF fender and repaired it. And yes I did mean the auxiliary air valve. For now seeing how it's idling smooth and pulling strong I'm going to concentrate primarily on the cold start issue and then backtrack on the 02 sensor thing. Is it possible just to be a bad 02 sensor? Once disconnected a whole host of issues cleared up,ie, surging at idle, surging on acceleration (v.minor), and overall engine smoothness. I think once I straighten out the cold start I'll take it to the local garage for a dyno emission run just to see what the 02 reading is. Fuel consumption is good as is oil and the tailpipe matches the plugs, a nice tannish/brwn. So I'm happy for now:), How is yours running? On the sly...word has it that a 87 Verde will be parted out here on the Island. I've seen it. Mechanically absolute correct w/ a strong body but rotten underneath. It should offer up something for everybody, cheers, Joe
 

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Hey Joe, nice to hear your comments again, how are you doing, I am still waiting for the Milano parts I asked you about, only kidding, because I sold the Milano Platinum last week :-( but I am for a hunt to a Verde, if you see anything good let me know.
When are you visiting Boston again?

Ciao for now!!!
Giorgio
 

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Joe, when you disconnect the O2 sensor you are running in open loop. As long as the air-fuel mixture is within a certain range, the car would runs happily (well, those who follows you might have other opinions :D !). The L-jet ECU (having less features) would not (from what I've seen) detect a disconnected O2 sensor and put up a CEL (Check Engine Light). With the O2 sensor disconnected, the ECU sees a 0 volt signal - which means too lean. The ECU would most likely just enrich the mixture to max compensation (a few percent?).

Cold start problems are also very likely related to air leak. A warm engine can tolerate and smooth things out easier. I got a cold start problem all a sudden a couple months ago. Idle was rough until car was warmed up. I tried doing various adjustments but the problem persisted. Finally, I took the plenum off and found a hair line crack in one of the rubber connector. Swapped in another one and the problem was solved!

You can "tap" in the O2 sensor signal wire (e.g. using a paper clip) to get a feel of the O2 signal output. If you use an analog voltmeter, you can see the needle swing between .2 to .8 volts in a few cycles per second. If you use a digital meter, then you are taking snap shots of readings within that range.

Bob
 

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Bob, thanks, I'll concentrate then on hunting for more air leaks. Giorgio, I saw that you sold it! The more I looked at it I was thinking welllll.....maybe....for a donor. But then it sold. Good thing. I can't do a 3rd car now. There is a Black Verde for sale here on LI at the local Alfa shop. Body, Interior, engine compartment looks good but I have not heard it run. The shop owner claims he put a bit into it to straighten it out. I believe him. Might be worth a look, Joe
 
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