Problem with making engine run

[[email protected]]

Hi I had a bad miss fire. Had a friend put his scanner on it and showed bad tps sensor,coolant temp sensor, Changed both with oem Delco
Started truck 1997 Tahoe 5.7 and still ran bad with rough idle. Put scanner on again now showed bad maf Changed that . Now truck will not start at all and shows no codes
???????????????????
Thanks in Advance for any help Wife is going to kick me out or kill me

 

[Erik the Awful]

Got spark? Got fuel pressure? You have to start your diagnosis there.

 

[Supercharged111]

And what was the data showing that made you throw a MAF, TPS, and ECT? I'm with Erik, if it won't start you're likely not getting spark or fuel.

 

[thegawd]

double check that everything is connected right and you can always put the old parts back on unless they are indeed garbage.

 

[Schurkey]

Had a friend put his scanner on it and showed bad tps sensor,coolant temp sensor... ...Put scanner on again now showed bad maf Changed that .

Scan tools don't really tell you that the sensor is bad. They tell you that there's a problem with the sensor circuit. The circuit includes the sensor, wire harness, and even part of the ECM.

The fact that the MAF didn't show up as a problem until after you replaced two other sensors makes me suspicious of the scan tool and the ECM.

Was your sensor diagnosis based on LIVE DATA or CODES? Codes can be useful, live data is essential.





Yeah, find out for certain if you have spark, proper fuel pressure, and verify that the live data on the scan tool looks right.

 

[[email protected]]

Finally found out what problem is. My msd box went bad .So that is 2 msd coils and one 6al box money down the toilet.
Guess they don,t care much about quality .all this happened within 3000 miles. But now it is fine for now but not much faith in MSd

 

[Frank Enstein]

MSD can repair the box. 915-855-7123

Unless you a have higher compression ratio than stock, are supercharged, or are running nitrous oxide you don't really need the box

 

[Schurkey]

Finally found out what problem is. My msd box went bad .So that is 2 msd coils and one 6al box money down the toilet.
Guess they don,t care much about quality .all this happened within 3000 miles. But now it is fine for now but not much faith in MSd

You didn't think to tell us you had an MSD spark-box on the truck in the first post you made?

I've had multiple MSD box failures. There's a reason MSD sells a switch that allows racers to choose between two MSD boxes--when one fails during a race, they flip the switch to the other box; hopefully before the car comes to a complete stop.

MSD can repair the box. 915-855-7123

MSD can repair at least some boxes. If the box was potted, as a moisture- and vibration-barrier, you're SOL.

Unless you a have higher compression ratio than stock, are supercharged, or are running nitrous oxide you don't really need the box

The boxes that include a rev-limiter are useful. The rest are just ballast--except as you noted.

I used to be a big believer in MSD; but I've had too many failures, seen too many rusted MSD distributors, and heard of too many failed MSD ignition coils. There's a little Stonehenge in my garage of MSD boxes; only one car in my fleet still has a box attached.

 

[Supercharged111]

MSD can repair the box. 915-855-7123

Unless you a have higher compression ratio than stock, are supercharged, or are running nitrous oxide you don't really need the box

Both of my trucks have blowers and stock ignition components.

 

[[email protected]]

Thanks for the feedback on MSD nice to know I am not alone on this