| Author |
Message |
James Selevan (Jselevan)
Member
Username: Jselevan
Post Number: 293
Registered: 6-2002
| | Posted on Wednesday, January 01, 2003 - 11:11 am: | |
Dave - didn't realize you were so close. After the New Year, let's try to meet at the donut shop in Huntington Beach Saturday morning. It is a very early Saturday (5:30-6:00 am) to get a place to park, but a nice collection of muscle cars and others show up there every Saturday. I will likely be there this coming Saturday (depending on the outcome of the BCS Bowl game Friday night - I am a Miami fan). By the way, Bill FINALLY finished my 30k service, and the car runs GREAT. Engine bay is showroom, and every washer is original equipment (including exhaust). Donut shop is on Magnolia and Adams. I can give you directions if you need them.
Jim S. |
DaveE (Banzaiboxr)
New member
Username: Banzaiboxr
Post Number: 26
Registered: 8-2002
| | Posted on Tuesday, December 31, 2002 - 8:39 pm: | |
James-I was at Enzo Motors Monday and did see
your Boxer.I will be updating my Injectors as
well.Bill informed me of updates that i was not
aware of.Also i will be replacing the D-cap.
I have the problem of unballance spark on
2 cylinders and loosing power.Bill will be
working on my car Thursday.
Hope to meet you sometime.
Dave |
James Selevan (Jselevan)
Member
Username: Jselevan
Post Number: 291
Registered: 6-2002
| | Posted on Tuesday, December 31, 2002 - 7:41 pm: | |
Greg - I watched as Bill Gojkov at Enzo motors did the diagnostics. He inserted the appropriate pressure gauges. Each fuel pump supplies separate halves of the engine, although there are crossovers. In my case, there were two problems. First, the pressure regulators were not equal, with one 9 pounds below specification, the other 4 pounds. Four pounds would likely not have resulted in symptoms in the absence of the other regulator being out 9 pounds.
The second culprit was the failure by Bosch to include the spring and ball check valve on the banjo that attaches the pumps to the hose. This was, apparently, an upgrade to these pumps called for by Ferrari in the mid 1980s. This prevents pressure leak-down during the 1st hour following shutdown.
Again, while cold, the cold circuit adds more fuel, and this is why starting overnight was not an issue. While hot, there was sufficient fuel pressure to start. It was the 30 to 40 minutes restart that resulted in an engine that would turn over and over, without apparent spark - but it was without fuel. The spark was fine. Just no food.
Hope this helps.
Jim S. |
Greg Rodgers (Joechristmas)
Member
Username: Joechristmas
Post Number: 571
Registered: 3-2001
| | Posted on Tuesday, December 31, 2002 - 7:05 pm: | |
Thanks James. Yeah maybe. I guess I will need to get a pressure tester to know for sure. It is a strange problem. On your TR was the problem in the fuel pump? Did you pressure test your entire system to diagnose? Also if you have 2 fuel pumps one right after the next how would could tell which one was causing the issue. Thanks. |
James Selevan (Jselevan)
Member
Username: Jselevan
Post Number: 290
Registered: 6-2002
| | Posted on Tuesday, December 31, 2002 - 3:26 pm: | |
Greg - I do not believe, from the symptoms described, that this is an electrical problem. Nor do I believe that a component is drawing too much current ("I am trying to think of anything that could be taking up all of the current"). What I am suggesting is that a component in your Fuel Injection system (pressure regulator, fuel pump, etc.) is allowing pressure to bleed off during shutdown, AND is not maintaining the correct pressure immediately upon starting. Once running, or with your voltage boost from the charger, you provide enough "over voltage - 13.8 volts" to your pumps, with subsequent pressure rise, to overcome the mechanical pressure deficit. The pressure should be within specification at 11 volts. It might be within specification at 13.8 volts. The problem is mechanical (injection), not electrical. It is fuel starvation, not absence of spark.
Just my thoughts arrived at from very similar symptoms in my TR.
Jim S. |
Greg Rodgers (Joechristmas)
Member
Username: Joechristmas
Post Number: 570
Registered: 3-2001
| | Posted on Tuesday, December 31, 2002 - 11:52 am: | |
Thanks for the info. James I agree it could be drawing more than normal. That makes sense. Now the trick is to find out which component is causing the problem. I checked the timing 15 BTDC, new NGK plugs, 12V at coil. If the coil was not functioning properly why would it fire instantly when warm or even if it sits for 2 hours it will still fire right up. Just the first initial start of the day gives the problem. Thanks Again for the info. |
JRV (Jrvall)
Member
Username: Jrvall
Post Number: 486
Registered: 11-2002
| | Posted on Tuesday, December 31, 2002 - 11:32 am: | |
>>Since the battery charger needs to be on for the car to stay lit <<
This part doesn't make sense unless the old battery has a dead cell or two and really doesn't make sense in that case in an after the starter has stopped drawing condition.
The starter could rob voltage from a coil during cranking, but it can't rob voltage after it stops cranking. However if the battery is weak, the Alternator "could" be creating a load on the crank by full fielding just after start-up.
However, that still doesn't explain why the engine doesn't just fire up with the cold rich running condition and achieve high idle with the extra air from the Aux. Air Valve.
Could be timing, wrong plugs, bad/weak coil, low coil voltage...but without knowing 'everything' about one system it's difficult many times to seperate cause from symptom. |
James Selevan (Jselevan)
Member
Username: Jselevan
Post Number: 289
Registered: 6-2002
| | Posted on Tuesday, December 31, 2002 - 11:25 am: | |
Greg - you describe the banjo part exactly. It sits between the pump and the accumulator.
As far as (possible) low voltage leading to injection system failure, this implies that the pressures are barely adequate with the charger/booster connected. The pressures should be within specification for the anticipated drop in voltage during starting (11 volts + or -). That you need to maintain 12 or 13 volts during starting implies that the higher voltage compensates for some system (pumps, regulator, etc.) failure.
Jim S. |
Greg Rodgers (Joechristmas)
Member
Username: Joechristmas
Post Number: 569
Registered: 3-2001
| | Posted on Tuesday, December 31, 2002 - 10:32 am: | |
Since the battery charger needs to be on for the car to stay lit when cold would this indicate that the alternator upon cold start up isn't providing adequate voltage? If the battery charger is not on the battery it will still turn and fire but after about 4 secs. it will stall as if it doesn't have enough power to run the FI. How much power is required to run the FI? When the charger is on it the car fires and will stay lit and I am thinking that the charger is giving the necessary power to keep it going hence why the car can't be started without it. The battery charger makes the difference as I have run this test numerous times. I remade the grounds from the battery to the engine and engine to chassis. I am trying to think of anything that could be taking up all of the current. Yes this Esprit has Bosch CIS K-Jetronic FI with Lambda. Yes I had a hot start issue on my 308. It would start great cold and right after it was turned off when hot but if you let it sit it would vapor lock. It took me a while to find an external check valve that would fit into the connection between the fuel pump to the accumulator. I didn't want to cut it up and use a banjo. I did find it and it replaces the union between the fuel pump and the fuel line to the accumulator. It is a hard to find part though. Thanks Again for the help. |
James Selevan (Jselevan)
Member
Username: Jselevan
Post Number: 288
Registered: 6-2002
| | Posted on Tuesday, December 31, 2002 - 9:41 am: | |
Just completed a Sherlock Holmes exercise into similar symptoms. This at the completion of an engine-out 30k service. Engine started fine when cold. Started fine when hot. Did not start after 30 minutes of cool down.
Pressure regulators, accumulators, fuel pumps, filters all new or rebuilt by Bosch. It was obvious by symptoms, and confirmed by pressure measurement that pressure was bleeding off too quickly upon shutdown. During cold start, as JRV suggested, Bosch richens the mixture. During hot start, pressure was still adequate.
Culprit proved to be rebuild of pumps by Bosch. They left out a little spring and check valve. Once identified and replaced, symptoms disappeared.
By the way, the regulators were rebuilt by Bosch, without success. These apparently (in the 512 BBi) are adjusted with a "Polish Micrometer" during importation and certification. Most certification shops apparently hammered down an adjustment point on the regulators to achieve a lean mixture (for smog certification). Bosch was unable to rebuild these to original specifications. I had to purchase two new ones.
Jim S. |
JRV (Jrvall)
Member
Username: Jrvall
Post Number: 484
Registered: 11-2002
| | Posted on Tuesday, December 31, 2002 - 9:14 am: | |
Billy, The Lotus he's asking about has CIS.
1) Of course you can run an Alt. without a battery...hook up a race car kill switch without the ceramic piece?? (too early for class without my notes haha) (Ohhh ballast resistor...yea it's all in there somewhere...) and run the car while you trip the kill switch...the engine will continue to run even though you have effectively disconnected the battery from the car, however you stand a chance of burning out the Diode Trio from overheating...and on later Heavily Electronic cars you stand the chance of spiking a diode or resistor on one of the circuit boards, the battery acts as a shunt or dumping zone for extra electricity. Doesn't mean it always happens, just that it can potentially happen.
2) extra battery/alt theory..it's a british car Greg is asking about, not a Ferrari, they have a different type/brand Alt/Reg than Ferraris, and if it was simply low voltage to the coil, it probably wouldn't start at all imo. Although you are correct that low coil voltage has not been definatively ruled out, but the extra battery is just a theory also, I'm not there so I can't tell if it is really helping or just seems to. But it a good idea to just go ahead and spec one entire system and define operating condition, before jumping to a different system to keep crossed/misinturpreted signals to a minimun.
3) Hold Pressure...yes you're right that 45min or 1 hour probably is irrelelivant..no I don't hold the specs in one hand and a stop watch in the other...the specs are guidelines...books tend to leave all the "well sorta like this" comments out and just tag a number to things so that newbies have definative specs to check against. However, for cold starting it helps if the system is full of gas (not neccesarily under pressure) to minimize the time and amount of fuel it takes to 'pressurize' the cold system, so hold time effiency does play into that as well(remember the system is built around pressure).
So Billy, what we have here is your typical easter egg hunt...and since we don't know what it is that causes the problem, it's faster and easier to find out what's not causing it, so we can home in on where the easter egg is hiding. You start with the long list and cross off items as you go, which leads to the short list. Not only that, on older cars it's not that uncommon to have more than one problem at the same time, however the human mind lkes to think in singularities, so by specing entire systems when multiple contributing problems exist, they can all be uncovered. |
billy bob (Fatbillybob)
Junior Member
Username: Fatbillybob
Post Number: 123
Registered: 8-2002
| | Posted on Monday, December 30, 2002 - 11:48 pm: | |
JRV,
I always need to know what Bosch system I working with. Sounds like a CIS. They all have different trouble shooting. However, That said " is the problem spark or fuel". I am not convinced from the posts that that has been determined.
JRV says: "The whole Bosch System is built around "Pressure"...normally, checking Cold/Hot, Running & System Pressure along with Hold Time Press. is the first step. "
Hold pressure is an interesting point. Many manuals on many CIS and other jectronic systems list hold times something like 30mins to 1hr. So for example if the book says hold for 1hr where is the cutoff for when you junk a presure regualtor or check valve? Does it really have to be 1 hr? How about 45 mins? Doesn't the system just need to hold pressure for the most probable time of vapor lock which hold pressures try to prevent?
JRV says: "I suspect the extra power reduces the load of the Alternator Charging."
Very interesting theory. Why not start the car without the alternator to see what happens? I never really understood how the alternator circuit works. If the car runs the alternator charges the battery and runs the electronics. No electronics draws from the battery? If no on battery draw then your theory can make sence. If the electronics runs from where ever it can draw like the alternator or the battery (which is just like a pot of free charge) then your theory does not work. I also never understood why you can't run a modern EFI car off the alternator and disconnect the battery. They always say ever run the car without a battery ...e=why is that?
Signed...
Electrically challenged |
JRV (Jrvall)
Member
Username: Jrvall
Post Number: 473
Registered: 11-2002
| | Posted on Monday, December 30, 2002 - 7:36 pm: | |
Greg, The whole Bosch System is built around "Pressure"...normally, checking Cold/Hot, Running & System Pressure along with Hold Time Press. is the first step.
Try Baum Tools for the standard Bosch Tester and adapters.
|
Greg Rodgers (Joechristmas)
Member
Username: Joechristmas
Post Number: 568
Registered: 3-2001
| | Posted on Monday, December 30, 2002 - 7:22 pm: | |
Thanks for the info. I agree it would be much better to know the pressures. I will look for a good pressure tester. I just wasn't sure if it was anything fairly obvious or not. I will check all of the voltages at the various FI components. Thanks Again. |
JRV (Jrvall)
Member
Username: Jrvall
Post Number: 470
Registered: 11-2002
| | Posted on Monday, December 30, 2002 - 7:13 pm: | |
Greg, I suspect the extra power reduces the load of the Alternator Charging.
Did you check voltage to the Aux. Air Valve to insure it opens and closes properly?
If the CS Inj. is squirting gas then it sounds like Fuel Pressure. Before replacing anything else make sure everything gets power...then like Tom says...checking Fuel Press. Cold and Hot is mandatory to gain enough info to proceed.
|
Greg Rodgers (Joechristmas)
Member
Username: Joechristmas
Post Number: 567
Registered: 3-2001
| | Posted on Monday, December 30, 2002 - 7:07 pm: | |
Oh yeah, I tried resetting the throttle jacking capsule to different high idle speeds and that didn't effect it. TPS is set as well. |
Greg Rodgers (Joechristmas)
Member
Username: Joechristmas
Post Number: 566
Registered: 3-2001
| | Posted on Monday, December 30, 2002 - 7:06 pm: | |
Here are some of the items I checked. Thanks for the info guys. I did set the mixture with a CO machine to about 1%. The cold start injector is firing. I removed and tested the thermal time switch and it is operational as well. I replaced the aux. air valve with a new unit and it made no different. I don't have a pressure tester so I am not sure of the fuel pressures at the pumps or at the WUR. The odd thing is that it starts fine when warm and fires instantly. I am pretty sure it isn't leaking down as fuel is there upon start up and the accumulator isn't leaking any fuel through the vent line. Why would the extra amps from the charger make the difference between it staying lit and stalling out? It seems that it needs extra power to keep it running. Thanks Again. |
JRV (Jrvall)
Member
Username: Jrvall
Post Number: 469
Registered: 11-2002
| | Posted on Monday, December 30, 2002 - 6:59 pm: | |
I don't think you have a battery issue. I work on an Esprit for a Lambo customer(and a Boatload Full of Bosch Inj. Cars). The Aux. Air Valve, Aux. Fuel Press. Regulator & Fuel Press. & Thermal Time Switch & Cold Start Injector all have to work right & simultanisly and the Static Mixture Adjustment at the Fuel Distrib has to be set correctly for any Bosch System Car to start properly cold.
The Cold Start Inj. fattens the intake air, the Aux. CS Press. Regulator Richens Overall Mixture, The Aux. Air Valve adds air for high idle and the Thermal Time Sw. Turns on the Cold Start Inj.
|
Tom Bakowsky (Tbakowsky)
Junior Member
Username: Tbakowsky
Post Number: 124
Registered: 9-2002
| | Posted on Monday, December 30, 2002 - 6:05 pm: | |
sounds to me like your cold start fuel pressure is out of wack. Trouble is trying to find out which componet is at fault. These system are kind of tricky to trouble shoot without propper fuel pressure gauges. But fuel pressure would be the first place I would look. |
Greg Rodgers (Joechristmas)
Member
Username: Joechristmas
Post Number: 565
Registered: 3-2001
| | Posted on Monday, December 30, 2002 - 5:57 pm: | |
I was wondering if maybe you could help me with this problem. I have tried many things and still can't get it to start right. When I got to start my Bosch Injected Esprit it fires up then stalls. If I put the battery charger on it for the first crank it will start and then slightly bog around 500 rpm after about 20 secs. it is ok and idles at cold idle. If I don't use the charger it doesn't seem to have enough power to keep running. (seems like fuel is being cut off) I have a new Optima Battery. It is in good condition. The battery charger seems to give it the extra boost it needs to stay lit. I also made a new ground from the starter to chassis. Any ideas? Happy Holidays. |