starts then dies

[roger longman]

The other evening I was caught in crawl/stop traffic for about 45 minutes, ambient around 60F. saw that the temperature gauge was reading 221F. ambient, a little high but, nothing to worry about, I thought. WRONG. Pulled into the store parking lot, shut off cleanly. Came back 20 minutes later, she started, ran for about 3 seconds with cronic pre-detonation (ignition, pinking), spluttering and then cutting out. Tried again, about 10 times in the next 25 minutes, same thing, gauge reading 211F. Called AAA. The guy got there in 30 minutes, asked for the key, I said "let me crank it once more, it'll probably start now you're here". YUP. Drove home (no traffic), put the 'magic' key in the following day, fans kicked in, haven't had time to look further yet. Symtoms, to me, are of over heating but how? What am I missing about the gauge reading ? Any ideas or thoughts would be much appreciated.......Roger.

 

[roger longman]

Hi Oz, Sorry, by 'magic' key I meant the one to pull the codes. AC was off. I was just checking that the fans were working......Roger.

 

[roger longman]

Anyone ? I'll pull codes tomorrow.........Roger.

 

[gmjunkie]

Anyone ? I'll pull codes tomorrow.........Roger.

Well it's kinda hard sometimes to diagnose a problem if you don't know IF there is any codes or What the codes are IF there are!So perhaps that would be best!~!!


Now that I've looked at my Gypsy Witch Cards and consulted my Chrystal Ball,They say you should probly check the fuel pressure too!(88/L98 34-39lb) Sometimes fuel pumps will act that way on and off for weeks,then 1 day crap out while merging in I-85/I-75 traffic in downtown Hotlanta at rush hour!~!!

 

[Hib Halverson]

In stop/go traffic and ECTsof 221 is not "overheating".

To offer any useful information we need a better description of the symptoms other than "pre-detonation" (no such thing), ignition (which is normal) or "pinking" (whatever that is).

Any DTCs set?
As GMjunkie suggests, run the fuel pressure tests in the FSM then post the results.

 

[boomdriver]

Let me know when you pull the code 33 & 34

As Junkies crystal ball says....I heard it too, fuel pressure.



whats pre-detonation?

 

[roger longman]

Hi all, sorry, TYPO, should have read 'detonation - pre-ignition'. Pinking is what Brits call what Americans call pinging,same dictionary definition. Showing NO codes and running normally but haven't taken it on a 'run'. I realize a lean mixture can cause it, fuel test was spot-on a couple of weeks ago (I know things go wrong in an instant) and will re-check when able.Thanks for your pointers, are there any more ?......Roger.

 

[roger longman]

Also, coolant level is correct !......Roger.

 

[boomdriver]

well....no codes says as much as having a whole list.....

Pinking 'eh... sounds like something done in the Do-Da parade...:ugh

if it were lean the o2 senor(s) would be sending all kinds of error signals and setting codes..

Could the base timing have slipped? the dist turned too far advance? Another symptom would be the starter struggling when its warm.

If the timing is ok, then the next place I'd look would be at the o2 sensors themselves...they can set bad codes, that the ECM will see as a rich condition and then shorten the inj pulse to attempt to compensate. That can happen from other system failures as well, but something usually sets a code.

Ck timing and O2 sensors.

 

[John Robinson]

Reaching back into my memory of how cars ran before all the ECM's and systems I remember vapor lock. Now I know that was a long time ago but have you done anything that could have moved a fuel line closer to the exhaust manifold. It does not matter if it is vapor lock or not but it does make me think as others have suggested that the fuel system needs a good looking at. Outside of that my next idea is the TPS. Before mine went bad I had the same thing happen I was on a trip and stopped to eat. When I came out the car would not start so I poured water onto the fuel lines and regulator and it started right up. This happened several weeks before one day at a stop light the car died. The problem was a bad TPS telling the ECM things that made the ECM shut down the fuel pulse. Oh and I did not get any codes with this.

 

[9340Ruby]

I had the same symptoms on my '93. It was the fuel pump for me. Hopefully you figure it out.

 

[roger longman]

Thanks Boom, John and Ruby, Checked timing, it's correct. Fuel lines are per factory. O2 sensor, changed a few weeks back, for the smog test. The one that came out looked fine, as did all the plugs. Starter cranks really well. I did set back the TPS, at that time, to .48, on John Banners advice. Could this be a possible cause ? I still thimk there was some drastic overheating, as exhibited by the symptoms. But how ? I dont know Do- Da, could it be Doo-Dah (as at Pasadena) ?.. For reference to pinking : see Thermal Engineering, page 1081. by R.K. Rajput.... It'll be after Christmas before I can check the fuel pressure and, I'm worried about going any distance, as I have a nagging suspicion that these things dont cure themselves !.:nono.....Roger.

 

[boomdriver]

The thing about temps is that what YOU see is not necessarily what the ECM is seeing. With several senders and none interconnected...you get your display off of 1 then the ecm gets info from another...so one can be bad and the other not.
If you have the 2 displays...see what the difference is. In mild weather it should not have to get over 210 degrees with fans running and you can run up to 250 before damage starts. If it were going to knock from temps....that would start a little over 200 depending on the fuel quality.
Poor spark quality can cause knock also. Bad wires...bad contacts.
Do you have a vac pump and a dental mirror? Your EGR may be stuck...that is where combustion cooling comes from when it gets hot enough inside to ping.

Test EGR by applying a vac (sucking on the vac hose is good enough) and looking under the diaphram to see if it moves or not..Don't always set a code either. If we already covered EGR...sorry for the repeat.

 

[roger longman]

Thanks Boom, I have already changed the EGR, for the smog test, the pintle on the old one was actually broken! Your point about the reading is well taken as, I've had it up to 235F, in summer in Arizona, with no ill effects ( except my heart rate, as that was the first and only time I had seen it go that high). Oh no, there was one other, when the alternator went bad and, it blew a hose. But never have I experienced pre-ignition (or knocking). Plugs and wires are good, I'm wondering if a bad coil is the issue?......Roger.

 

[boomdriver]

Thanks Boom, I have already changed the EGR, for the smog test, the pintle on the old one was actually broken! Your point about the reading is well taken as, I've had it up to 235F, in summer in Arizona, with no ill effects ( except my heart rate, as that was the first and only time I had seen it go that high). Oh no, there was one other, when the distributor went bad and, it blew a hose. But never have I experienced pre-ignition (or knocking). Plugs and wires are good, I'm wondering if a bad coil is the issue?......Roger.

I think yours has the ESC module by the washer bottle...if it were a real 'knock' the knock sensor should retard it enough to end it..unless its already at the end of its window. Ping is caused by something that glows red hot and causes the fuel charge to ignite early...premature ignition. Carbon deposits can do that, improper spark plugs that are not transfering heat away and retaining sufficient heat to pre-ignite.
Weak spark does it...causing poor combustion or partial combustion....(knocking) similar noise with a different cause. bad fuel, bad spark..

Either condition is more likely at higher temps but NOT impossible at lower temps. I had some new wires that caused it at any temp if I stood in it under a load.

I dunno...hard to do more than list the possible causes, not being there.

Even if the car is not quite right,
Have a Merry Christmas anyway !

 

[John Robinson]

Boom has opened up a whole new question. Did this start shortly after filling up with gas.? And if so are you still using that tank of gas? Water in the gas will cause the engine to run poorly or to ping as you say from the moisture turning into steam during the combustion process. If not the gas has the car been kept were it is very humid such as outdoors during a rainy day or two. That could lead to moisture accumulating in the tank especially if the tank was less than half full. Water in the tank from any source can cause severe damage to the engine. I had a friend who was on a trip and pulled in and filled his car with gas. Less than a block later the engine detonated. When they pulled the gas from the tank it had over a gallon of water in the gas. Since the engine was hot from having been run for several hours that amount of water hitting the hot pistons etc turned to steam and blew the engine apart. If this is what you find has happened then I think you have found the overheating problem as well.

 

[roger longman]

Thanks Boom and John, I'll be checking out the coil etc. next week. The gas wasn't new. A point is, this happened on the return leg of a trip downtown (something I do as infrequently as possible), when I was caught in the rush hour and, unlike the first leg, had crawl and stop traffic, resulting in a gauge reading of 221F, not high but higher than I've had before around here. Engine was running fine, it was only after a stop, of about 20 minutes, that the problem occured. Anyway, a very merry christmas to all.......Roger.

 

[roger longman]

I reset the TPS to .54 and, did an 'intown run'. Fine on the way out but, on the return, caught in traffic, I had to slip into neutral every time, before stopping, to keep the engine running. Another 'run' of about 40 miles she ran fine. I'm guessing the problem had been an ECM learning condition. Fuel pressure is good,so I'm still trying to figure out why the problem occured in the first place. Any ideas will be appreciated.......Roger.

 

[FForward]

Check your injectors.....had similar problem as yours.....car ran fine....went in store and wouldn't start afterwards......several attemps to start failed.....tow truck came and I tried starting again....it started......started several times after that too......I checked injectors.....several were below specs......changed them and no problems since then......just a thought.....they are easy to check.....Good luck!.....Bill

 

[roger longman]

Hi Bill, I initially spoke to John Banner, about this and he just about ruled out there being any problems with the injectors on an '88. The plugs looked fine but I'll check again.....Roger.