Dies and wont start back up for 5-10 minutes
Ok, I hope some of you guys can help me out with your jeep wisdom.
A little bit of background, I've got an 83 with the 258. It had a Howell TBI on it when I got it. Recent upgrades include Team Rush, new ignition coil, new ignition module, and new plugs and wires. I recently advanced the Initial Timing a little from 8* to 10* ( I live in Colorado at about 5000').
The problem: Occasionally when I'm driving, coming up to a stop sign or light, I'll take it out of gear, coast, then brake to stop. Sometimes when I do this it just cuts out and dies on me as I begin to coast. I used to be able to just turn the key and crank it over again without any issues. But now it wont start after it dies. I have to wait 5-10 minutes for it to start back up again. In order to get it to start I have to crank and crank and crank with the skinny jammed to the floor. When it starts to come to life, I have to continue to hold the key in start until it chokes to life enough. It runs really rough at first, then almost like clearing its throat, it runs fine. After I get it started this way, I've shut it off and started it again several times in succession without any issues.
Any suggestions on what I should be trying to troubleshoot. I've already changed all the ignition components I thought were the issue. Thanks
It sounds like a vapor lock issue to me. When it dies, and doesn't start, are you getting gas to the carb as it cranks?
when it dies, as soon as possible, pump carb with your hand and see if any gas is sprayed into carb.
if yes, then you may have an electrical problem, when the componet in question gets hot, it opens up and kill the circuit.
if no, then as matt said you are having sometype fuel stopage, change fuel filter,
my old jeep blew a fuseable link up by the firewall one day, why i do not know, but got my book out and found it, wired in a heavy duty fused link, so far no more problems,
buy you a top quality repair manual, if you do not have one, you will need it later, if you keep the old jeep.
post what you find wrong, someone else will have the same problem someday and need you help.
Is the Check Engine light on on the TBI? Do you have descent grounds for the Ignition module? Any chance of checking spark once it stalls?
I'm not a mechanic .... but I stayed in a Holiday Inn Express last night! ... just kidding. I know this sounds kind of simple but I had the same problem with a 2000 Chevy truck. It was the fuel pump! Grab a gauge and check your fuel pressure. I should have had 55 lbs + static on my truck and it was only about 20. I had trouble with 2 Ac Delco pumps and finally put in a Bosch ... no more problems. So far :)
You may have a bad main chassis power cable connection at your solenoid. If so, the problem is that after your engine first starts, the current flowing through the bad connection starts to heat up causing a high resistance condition. After a short while, the resistance becomes so great that very little current flow exist. Which means your ignition module no longer has the proper voltage and current to work correctly.
After giving the connection enough time to cool down, you can crank your engine again.
An easy way to see if this is the problem is by letting your engine run and then feel the cable insulation coming from your alternator towards your solenoid. If the cable becomes too hot to touch, then you have a bad joint connection where it ties into the chassis power cable and it needs to be re-terminated with a good solder joint.
This may not be the cause of your problem, but it was for my Jeep and it made a huge difference after it was fixed.
Thank you for the suggestions. I had it die again last night and couldnt get it started back up. Sitting in a left hand turn lane, cranking away until I exhausted the battery....:(
One thing I noticed, check engine light comes on when turned to run (as it should) but goes off when cranking. I need to dig out the Howell instructions, but I'm pretty sure that is no bueno. So I'm thinking I have a combination of issues going on here. When it heats up, something is becoming very resistive and not giving me the power I need for cranking. Continually trying to start it keeps cycling the fuel pump which keeps trying to prime the engine, which causes it to begin to flood (the rough start when it does finally start). I need to get it to die again and then throw the inductive timing light on the wire from the coil to the distributor and check if I'm getting spark. I'll let you guys know what I find out today.
I think your problem is a flooding issue. When you wait 5-10 min enough fuel has evaporated that it will start right up. This also explains why you have to floor the accelerator in order to get it to start. This allows for maximum air flow into the intake which helps with the flooding issue, however if you have a weak battery (like mine) you will run out of juice before it will fire. This is the same symptoms that my 258 with Howell TBI has when I stall it.
There should be a white wire that runs to your coil that powers the injectors, and fuel pump. If you disconnect this wire from the coil (this will prevent more fuel from being pumped into the intake) and crank your jeep over it should start right up and suck all the flooded fuel out of the intake manifold then die. Reconnect the white wire to the coil and it will fire right up again. This will help you get back on the road ASAP but does not address the real issue of why it is flooding in the first place. I have not spent any time trying to figure this out due to the fact that this would take time that I do not have to dedicate to it right now.
I do know that Howell is VERY good with customer service and tech support and I have no doubt that if you called them they would be able to help or point you in the right direction. I hope this help you along also.
ps - The check engine light goes out when I crank mine also. I think that is normal behavior...
codes stored even though i'm not getting a check engine light. It's been super cold lately so it's hard to work on it and get it hot enough in the driveway to replicate the issue.
Howell manual says the light should be on when cranking. Mine is when it starts cold.
This leads me to think I have an electrical problem with starting when it's warm and a mixture problem that is causing the stalling.
Ok so I was able to let.it idle until it started acting up this evening. I hooked up the timing light to check if i.was getting spark, which I am.
It looks like i'm getting too much fuel outbid the injectors. If I unplugged one of them it would start up again. So the question is what is making it run so rich?? Correct me if I am wrong, but I believe the sensors that go into the mixture input are the oxygen sensor, the MAP, and the coolant temp sensor. Is there any way to trouble shoot these individually? I still need to get a fuel.pressure guage and see what pressure I have going in. my return line was touching on the manifold, could this be causing any issues?
*UPDATE* I checked to see if it would throw any codes even though the light was coming on. Nothing but 12's
In case you didn't have them
To Display Trouble Codes:
Run a wire or paper clip from Pin A to Pin B then turn the ignition on but do not start engine. The "Check Engine " light will flash in the following sequence: flash, pause, flash-flash, long pause flash, pause, flash-flash, long pause flash, pause, flash-flash, long pause. This is a code "12" which will always be there and tells that the diagnostic test is working. After this series of flashes and pauses any stored trouble codes will now flash. If you do not see the "12" flash three times, your diagnostic circuit is defective.
Most vehicles will display stored trouble codes, then "12" again.
12. No reference pulses to Electronic Control Module (ECM). You will get this code when checking for error codes because the engine is not running.
13. Oxygen sensor signal stays lean during warm engine cruise, your O2 sensor could be unplugged or faulty wire.
14. High temperature indicated at engine coolant temp. sensor. Sensor could be unplugged or faulty wire.
15. Low temperature indicated at engine coolant temp. sensor
21. High voltage at throttle position sensor. Sensor could be unplugged.
22. Low voltage at throttle position sensor
23. Low temperature at manifold air temperature sensor
24. Circuit fault in vehicle speed sensor
25. High temperature at manifold air temperature sensor
29. Fault in 4th gear switch
32. Fault in exhaust gas recirculation valve diagnostic switch
33. High voltage (low vacuum) at MAP sensor.
34. Low voltage (high vacuum) at MAP sensor.
41. Cylinder select error
42. Fault at electronic spark timing circuit (sets when timing is set also, clear code and verify that it does not return.)
43. Low voltage at electronic spark timing circuit
44. Oxygen sensor lean
45. Oxygen sensor rich
46. Fault at vehicle anti-theft system
51. PROM error
52. Low voltage at oil temperature sensor
53. High voltage at battery
54. Low voltage at fuel pump OR Low voltage at Fuel pump relay
55. Problem at Electronic Control Module (ECM) - ECM failure OR Serial bus error
62. High voltage at oil temperature sensor
CLEARING THE TROUBLE CODES
Turn the key switch to the off position. To clear any trouble codes, disconnect the battery for 30 seconds or unplug the connectors to the ECM. If this is done at the battery, you may loose your preset stations on your stereo A better place to remove power is at the fuse.
I tested and didnt get any error codes. It just flashed 12 continuously.
I didnt get to work on it at all last night because some bonehead left the key in the run position and killed the battery.... :brickwall Not sure if I fried the ignition module or coil yet as the battery is still on the charger. We'll see if it runs any better resetting the computer. If not I guess the next plan of action is to start changing out the temperature, o2, and map sensors and see if things improve.
Ok, so I have a little bit of an update. I replaced the coolant, o2, and map sensors. None of these made any difference, now all I have is some spare parts.... Computer was reset after new sensor install. Thought maybe the injectors were sticking a bit, so took them out and soaked them in carb cleaner for a day. Again, this didnt really make a difference. Tried disconnecting the return line and letting that run into a gas can. Seemed to fill up the can rather quickly. Picking up a fuel pressure gauge today to test the inlet pressure. Also going to get a tach, as I never had one in there. It seems like when its warmed up and I coast the rpm drops really low, almost sounds like the jeep shut off, so I'm currious to know what my rpms are.
I've spent a good amount of time searching the forum and still cant come up with anyone who has had a similar problem that solved it.
Thing is with the TBI, almost all problems look alike. Stalling and hard starting. Since you didn't install the TBI, you're probably learning a lot but as someone who's installed one, there's nothing better than doing it yourself. Now your job is to retrace all the connections and find the problem.
There are two basic aspects to the TBI - good electrical connections and fuel delivery. An electrical problem won't necessarily throw a code, but a faulty sensor should by causing a rich or lean environment. You've already seemingly ruled out some of the electricals by replacing all of the sensors. A good place to start, but these parts add up and should've thrown a code.
Next thing I'd pay attention to is whether your fuel pump turns on when you're having problems. Listen for it to come on, sounds like a CD player accepting a disc. When I first installed mine, there was a bad connection at the fuel pump relay. The fuel pump intermittently worked, and eventually went strong for about 3000 miles. Then the problems started popping up again. I bought a new relay and there wasn't any improvement. Called Howell and they had me run through a few things and ended up sending me a new computer. In the meantime I kept at it and found out the connection pins for the relay - those in the actual harness, were loose. Must've happened when I had to take it apart to fit the harness through the firewall. I opened up the connections so they could get a better purchase on the relay, and the problem was solved. Make sure your fuel pump is turning on and that your connections there are good. $50-60 part to replace.
The other thing to check without spending anything is the fuel return line. Make sure it's patent by forcing air through it. If there's a return restriction, your fuel pressure at the injectors will be too high.
The proximity of your fuel line to hot surfaces could also be an issue, as noted in one of your posts. Try to get them up off of any hot surfaces or you could be running into vapor lock issues.
Other thing to check is your fuel filter. That system may have been in there long enough to have accumulated enough gunk to cause a fuel delivery problem. It's a $15 part.
Ruling out fuel delivery, next thing to check is all of your electricals. It only happens when warm, and when the RPMs are dropping, so it could be a matter of the computer getting enough juice. How is the power sent to the computer - straight from the battery through a fuse or through the fuse box? Straight from the battery is best, as it will supply a continuous source of power no matter what the engine is doing. From the fuse box, it could be seeing variations in power and shutting down when the rpms drop low enough. My radio will die when it's cold out and my engine is warm, my headlights and heater are on and I'm sitting at a stoplight for a while - the rpms drop and the voltage does, too - below 12v and the computer, radio, etc. need 12v of operating power to stay on.
It's a pretty simple system once you get to know it, and operates flawlessly when everything is connected well and you're getting fuel. Sorry for the long-winded post, but like I said, installing it yourself really helps troubleshoot any problems.
I know nothing specific to the Howell system, but what you describe is common over on the Cherokee forum. i have had this happen to my Cherokee too. 9 times out of 10 it is a failed or failing crank position sensor. On the 4.0 it is the one sensor that will kill the engine at any time. Just a suggestion for you.
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