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Discussion Starter #1
I'm down to what should be the last problem with this car, It has been an ongoing problem now I have finally been able to start diagnosing, the car occasionaly would have a hard start, you would crank and crank and after a few it would start then stall then do again and give a little gas peddel to clear it up once running or let it idle and it would run rough for a few and clear on its own, so yesterday I got down to testing some components.

I removed the spark plugs right after it started ruff, they all 4 where even with carbon leaving me showing a rich condition I suspected, I checked spark next during hard start, spark is fine and putting a plug on the end of a wire shows stong blue spark as it should be, next up checked fuel pressure was ok again and it still was next I started checking the csi and tts, I found the switch under 86f would spray and above 104f as manual stated would not spray, I removed the csi and under pressure does not leak and when it should spray it does and has a perfect spray pattern. After those tests cooling system was too warm to perform further testing plus I drove the car the entire day to make sure of no further problems.

Today I have found with the csi disconnected the car for at least the duration I tried starting would not start nor try for me, so I connected the csi back up and she fired right away, then stalled as normal, I crank again and the engine is now back at that point to hard starting I then as a test pull the csi harness connector again and she fires riht up with no hard start and from then on will start and run fine with no problems, cooling system still below 86f and outside air temp 69f.

Through what I have tested would I be wrong in my diagnosis thinking the csi is dumping too much fuel as it will not start without it but connnect it back and it starts and then stalls then hard start disconnect and it will start easy and run fine, so its getting a small burst to initial start of fuel from the csi as needed but when it stalls after first cold start I suspect its because the csi is dumping to much fuel thus flooding then its hard start after the stall, to further conclude my findings disconnecting the csi then prevents further fuel dump and the car will start easy and perfect everytime after unless back into cold start state or intermittant fault.

Tts.............. below 86f - 0ohms above 104f - 133ohms as manual states within specs.

Manual gives no further testing into how many durations the tts will engauge the csi, I'm wondering, because rational thinking from what is listed the system is working fine as below 86f the csi should release fuel for so many seconds, however I have a feeling this one is going on releasing fuel for too long, note I have not tested how long it sprays for yet. To me the csi is confusing as too much info is left out on how the system functions.
 

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You should be looking at the AAV it is the culprit from what you describe and/or air leaks.

You are forgetting that the TTS does not instantly reset. It retains residual heat from the internal heater for some time.

TTFN Elio
 

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Discussion Starter #3
You should be looking at the AAV it is the culprit from what you describe and/or air leaks.

You are forgetting that the TTS does not instantly reset. It retains residual heat from the internal heater for some time.

TTFN Elio
The aav has already been fully tested and was in correct working order, there are also no known air leaks I have found, air leaks do not only happen on cold starts, this problem is only there during the first cold start. I realize where you are coming from based on the aav system however I know for a fact through testing the aav does not leak and is in working order.

As well I do not suspect any fuel injector problems as all 4 plugs have the exact same carbon on them and if it where a injector problem and very odd for all 4 it would not only be on first cold start, once this car is running it runs perfect, plenty of pick up, spins tires in first gear, chirps in 2nd and power all through all 5 gears, never a hiccup, no vacuum leaks are known I have replaced all lines which means nothing however I have found no leaks as of yet.

Further suggestions?

Just an FYI I am a ase cert tech in automotive and marine with over 15 years experience. This is just my first alfa I have serviced and I am past the manual as it is not providing further testing info I need, The manual does not show anything further for the tts or csi it is very limited from what I have found or I have possibly overlooked. The problem is something I must fix correctly.

Thanks
 

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Are you aware or do you have Engine Maintenance Manual..Alfa publication (51 pages) for the bosch engine management system? pub #( PA 365100000000)
Pages 25 and 26 troubleshooting chart "Engine does not start or starts only with difficulty"

From what you have already tested they also list:

Fuel Pressure (2.3-2.7Bar)
Temperature sensor ll (2-3Kohms @ +20 deg C)

Best regards, Elio
 

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Discussion Starter #5
I waited for cool down and went out, with the csi disconnected the engine started easy, I connected the csi back up and there was a slight hesitation but the engine started had a tiny rough idle and cleared right up quick, however now once starting with csi connected the engine is back to starting just fine engine temp below 86f still. As I stated this is hard to trace/diagnose, as it is random, if I let the car sit a few hours or overnight it will have a hard start always unless you start then stall disconnect csi and it will then start perfect, no further problems until it sits for a full cool down again or over time, to me a cool down should be 86f or lower however I have not even reached that temp yet so it is very hard to diagnose this problem.

AAV when cold is open when warm is closed....... Along with all other aav tests listed the device passed each test as stated in specs..... Unless I am missing something.

What about the Engine coolant NTC thermistor?

For now I can only take suggestions for further testing until the problem occurs again.

FYI- I have another post on here showing all work already preformed, to relate to this problem I have replaced both fuel pumps, fuel tank, all fuel and fuel vapor lines, sending unit, fuel pressure regulator and so on, the only part not replaced is the fuel rail, csi , tts and the 4 injectors of which 3 years ago I replaced 1 injector that was bad. There is no current problem until next cold fresh start which I will go ahead and test injector pulse anyways even though I do not expect that as a problem based on all 4 plugs look the exact same and once running is just fine.
 

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Discussion Starter #6 (Edited)
Are you aware or do you have Engine Maintenance Manual..Alfa publication (51 pages) for the bosch engine management system? pub #( PA 365100000000)
Pages 25 and 26 troubleshooting chart "Engine does not start or starts only with difficulty"

From what you have already tested they also list:

Fuel Pressure (2.3-2.7Bar)
Temperature sensor ll (2-3Kohms @ +20 deg C)

Best regards, Elio
Yes, I have the complete manual that covers every part even body panel replacement.

Fuel pressure is correct or was 2 months ago but had this problem during that test as well, so since the problem was during that time and fuel pressure was correct then it was not causing this problem. I have removed the fuel pressure tester adaptor as fuel pressure was correct during koeo and koer and while driving so no further pressure tests where needed and it was removed after replacing a bad fuel pressure regulator ( pressure was not holding with key turned off, as soon as you turned key off the pressure would drop to zero right away, a quick fuel pressure regulator replacement resolved that problem). Also during initial prime, like your 2 sec prime after the prime pressure would drop to zero way to fast, the new regulator resolved this problem. This would not be a fuel pressure problem as it is only on a first time cold start, no further problems after first cold hard start.

I have not tested temp sensor 2 yet. I will have to find which one that is and convert c to deg.
 

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Discussion Starter #7
update:

I have had it cool down enough to hard start again, here are my findings:

Hard start with csi connected and working, it will start then stall then hard to start, next step disconnect connector to csi to disable it, then once disconnected engine will then start and run fine now hard start, turn engine off starts right back up as should next test connect csi back up, start engine and it stalls right back to hard starting again so disconnect csi and engine will start and run perfect, no hard start other then the excess fuel in the engine forcing a tiny excess crank to start and the smell of excess fuel from the exhaust proving flooding/rich fuel mixture. So my findings are so far a problem with the cold start system?

You can continue the above over and over again so long as engine does not get warm enough, once engine reaches a certain temp/prolonged running time this problem will no longer occur until engine cool down over time, now if you start it with the csi connected she will run rough at idle, give it a little gas peddel to clear it up and less then 5 mins running, hard start no longer there.

Can someone explain the csi and tts system more in detail so if I am looking something over? I have a feeling the tts may be running the csi too long thus flooding the system. Or something else?

Thanks everyone!
 

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Discussion Starter #9
This info is much more different then the Manufacture Alfa repair/diagnosis manual........

I will check as you have listed, for now I have already removed the csi and found it sprays a perfect pattern below 86f and none above 104f. tts shows correct ohms 86f and lower 0ohms and 104f above 133ohms.

To further give more detail the current temp now is now about 76f, now from a cold start if the csi is connected it is hard start, if you start off with csi disconnected it starts perfect connect the csi and she starts and stalls, this is different from this morning as it was about 68-70deg f and it would not start with csi disconnected you had to hook csi up and do one crank and let it stall then disconnect csi and it would start and run perfect, now at the current outside temp of 76f you can start off with csi disconnected and she starts perfect. Internal engine temo cold would not have changed too much during this time frame, let me go over the link you provided and see what I find.

Thanks,
 

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Discussion Starter #10
"Remove the cold start injector from the intake manifold, place the nozzle in a safe container and crank the engine. If the temperature of the engine is below 95 degrees, the cold-start injector should spray. If it does not, connect a test light to each of the two terminals of the injector and crank the engine.

If one terminal activates the light but the other does not, replace the cold-start injector.

If both terminals activate the light, inspect the wiring between the cold-start injector and the thermo-time switch. If the wiring is OK, replace the switch.

If neither terminal lights up the light, repair the wiring harness between the starter solenoid and the cold-start injector"

This doesnt really explain anymore that I can tell other then I already know, I know for a fact under 95f that the csi sprays fuel and at, at least 104f the csi no longer sprays........ So I do not think the above helps? Am I missing something?

It seems like the above tests are for if the csi is not spraying below 95f or am I wrong?
 

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csi and tts

So it seems that the CSI and TTS are working correctly.

So then the problem is someplace else, perhaps one of the main injectors is leaking and disconnecting the CSI leans out the mix enough for the engine to start.
 

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Discussion Starter #12
So it seems that the CSI and TTS are working correctly.

So then the problem is someplace else, perhaps one of the main injectors is leaking and disconnecting the CSI leans out the mix enough for the engine to start.
Good observation, however it only happens on cold first time starts never again....... Most cases a leaking injector will not cause just that, a leaking injector would do this during all starts and usually during running.....

However if there is anything that activates a "richer" mixture from the 4 injectors as well which should be after cold start csi then maybe that is possibly the problem?
 

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Discussion Starter #13 (Edited)
Lets think back to carbeuration, it uses a choke in most cases, when cold most times you need the choke and when warm out usually no choke is needed, were speaking outside temp not engine temp per say......... So in fuel injection, well more so in a 1988 alfa romeo spider veloce's case what has to deal with outside temp and rich/lean of fuel injectors? Eliminating the tps and aav both are known working as well as far as I found mass is also working correctly.

Once again this problem only happens on cold engine start and reacts a little different if outside temp is warm or cold, cold it requires 1 start off csi and then disconnect proves easier start then csi staying connected, when temp outside is warmer but below 86f or 95f lets say first start csi disconnected starts and runs perfect first try. I'm about to figure out a darn choke system to add with how closely this reacts to one.

There has to be something im looking over here related to an alfa that I normally do not come across on other types of vehicles? maybe something simple that I just don't know of.

Most have a temp sender for the gauge and or a light and another for the computer that usually acts to work with other parts of the system to richen the fuel system under cold engine conditions, but I only knew of the csi for cold starts on the alfa, and nothing for the normal injectors. I thought I remebered reading after the csi something works with to enrichen the 4 normal injectors as well?
 

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When the engine is cold, Computer is told to run engine rich. (Open loop) It ignores the O2 sensor.
Perhaps you have the throttle butterfly not completely closed, It should be adjusted to closed.
It is also possible that at start, the AFM resistor arm is not giving a correct signal. The resistors have been known to wear and have discontinuous readings. Also the AFM Bypass screw could be a culprit making the start mixture hard to start. Or ASM flapper could be sticking.
Is the Manifold vacuum line to the MAP sensor which sets ignition timing leaking or disconnected, sio you don't have correct advance?
Just some ideas...Elio
 

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Discussion Starter #15
When the engine is cold, Computer is told to run engine rich. (Open loop) It ignores the O2 sensor.
Perhaps you have the throttle butterfly not completely closed, It should be adjusted to closed.
It is also possible that at start, the AFM resistor arm is not giving a correct signal. The resistors have been known to wear and have discontinuous readings. Also the AFM Bypass screw could be a culprit making the start mixture hard to start. Or ASM flapper could be sticking.
Is the Manifold vacuum line to the MAP sensor which sets ignition timing leaking or disconnected, sio you don't have correct advance?
Just some ideas...Elio
I appriciate the ideas, they do help, I'm wondering though is this problem is only and only at a cold start with air temp outside lower as well at this point I know below 74 deg f....... Anything warmer and it starts fine so long as the csi is not connected and once engine is at temp the car starts perfect every time......

I know there are no vacuum leaks so far, where is a map sensor on this?

The AFM bypass screw I can assume is the one on the box where it is an allen head? If so the last shop drilled this hole larger ( to access the screw?) Its external the afm right front of where the duct attaches. The last shop which had no clue what they where doing did screw around with the afm. It does from my tests seem fine and looks like brand new inside still.
 

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Perhaps the CSI operates correctly when removed because it's at nominal 1 atmosphere, but when placed in the plenum, it's now at less than 1 ATM, and perhaps there is a dribble being sucked out. How easy to substitute a ( hopefully ) known good CSI?
 

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There are a number of things where you seem to be assuming they are good because they were replaced or tested good in the recent past. One thing our cars do not tolerate are assumptions... Verify.

The cold start circuit is fairly simple and also it is 'stand alone' (not under computer control). During cranking, power is supplied to the circuit. If the temp is below the set point the CSI should squirt. Once above that temp it should not squirt. The thermo-time switch has a built in bi-metal strip that cuts power (or the ground connection for the circuit) after electricity has passed through it for a short while. This keeps the CSI from squirting indefinately - typically for 3-8 seconds maximum depending on the starting temp.

IIRC, the TTS provides the ground connection for the circuit, thus it might be a good idea to confirm it is making a good ground connection. I assume (I know, I just said our cars don't like assumptions...) the ground connection is via the threads of the TTS. Perhaps loosening it and re-tightening it will improve that ground connection.
 

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Discussion Starter #18
There are a number of things where you seem to be assuming they are good because they were replaced or tested good in the recent past. One thing our cars do not tolerate are assumptions... Verify.

The cold start circuit is fairly simple and also it is 'stand alone' (not under computer control). During cranking, power is supplied to the circuit. If the temp is below the set point the CSI should squirt. Once above that temp it should not squirt. The thermo-time switch has a built in bi-metal strip that cuts power (or the ground connection for the circuit) after electricity has passed through it for a short while. This keeps the CSI from squirting indefinately - typically for 3-8 seconds maximum depending on the starting temp.

IIRC, the TTS provides the ground connection for the circuit, thus it might be a good idea to confirm it is making a good ground connection. I assume (I know, I just said our cars don't like assumptions...) the ground connection is via the threads of the TTS. Perhaps loosening it and re-tightening it will improve that ground connection.
Thanks, Actually the assumptions I have made of working parts even if they where replaced is because this problem was there still even when the other parts tested good thus showing none of what I had tested or replaced and tested at the time had to do with this exact problem.

Once engine is up to full operating temp the engine will start perfect every time.

What I know so far is that engine is running rich as all 4 plugs are carboned up and once started if csi stays connected we get blue smoke from exhaust and the smell of fuel. Disconnecting or connecting the csi proves to make the engine either hard to start or starts perfect.

I will preform some other tests tomorrow. Whats confusing me is this morning at just below 70f the car would not start without connecting the csi, let it start then stall then disconnect csi and it will start perfect, yet this afternoon around 75-76f it will start perfect first time with csi disconnected. So far outside air temp seems to effect the way it will start..................

Just went out right now to check, current outside air temp 65f, with csi disconnected engine started much better then with csi connected.

I guess its back to the drawing board in the morning.

Will try everything suggested.
 

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Discussion Starter #20
May we assume you have seen Step 3 in the L-jetronic diagnosis page?
Yes, that write up I actually found before this site, it has helped greatly in finding other problems, I however ignored the testing of the aav there and followed the service manual, so I am currently testing it that way now.

Cold temp> below 86f tests on tts and cts are all within specs, once I test the aav I will start and run the engine until above 104f and retest the tts, csi and aav once again.
 
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